<?xml version="1.0" encoding="UTF-8"?><rss xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:atom="http://www.w3.org/2005/Atom" version="2.0" xmlns:media="http://search.yahoo.com/mrss/"><channel><title><![CDATA[Astronewb]]></title><description><![CDATA[No Description]]></description><link>https://astronewb.herokuapp.com/</link><image><url>https://astronewb.herokuapp.com/favicon.png</url><title>Astronewb</title><link>https://astronewb.herokuapp.com/</link></image><generator>Ghost 2.9</generator><lastBuildDate>Sat, 21 Aug 2021 05:41:41 GMT</lastBuildDate><atom:link href="https://astronewb.herokuapp.com/rss/" rel="self" type="application/rss+xml"/><ttl>60</ttl><item><title><![CDATA[Trifid and Lagoon Nebula astrophoto + workflow and review]]></title><description><![CDATA[My finished photo of the Trifid and Lagoon Nebulae with processing details.]]></description><link>https://astronewb.herokuapp.com/trifid-and-lagoon-nebula/</link><guid isPermaLink="false">Ghost__Post__611b896eb457a7001cd37c45</guid><category><![CDATA[Photo]]></category><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Fri, 20 Aug 2021 05:57:12 GMT</pubDate><content:encoded><![CDATA[<figure class="kg-card kg-image-card kg-width-full kg-card-hascaption"><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/Lagoon-trifid-DSS-nodark-aff-jpg100.jpg" class="kg-image"><figcaption>Left: M20 Trifid Nebula. Right: M8 Lagoon Nebula.</figcaption></img></figure><p><em>For full resolution &amp; technical specs see the astrobin page <a href="https://www.astrobin.com/e7nobk/">here</a>.</em></p><p>Clear nights have been pretty sparse this winter but the start of the month offered one sandwiched between days of cloud and howling winds. Much of the opportunity was squandered as I burned a couple hours fretting over my camera which refused to fire its shutter consistently. Of course, when I was about to chalk it up as broken and head inside, I realised I hadn't plugged my usb hub into the mains! My camera's powered via the hub but it still sorta half works when the hub is only powered by it's usb connection to my laptop. I probably would've caught on sooner if the bloody thing just didn't work at all but it seems the minor details of the setup ritual can slip after being away from observatory for a while! All said and done I ended up capturing 1hr of exposures under clear, moonless skies and it was definitely worth it! I'm happy with the final image but I learned so much while processing. Read on to learn more about the objects and the processing applied to get the result.</p><h3 id="about-the-objects">About the objects</h3><figure class="kg-card kg-image-card"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/2021-08-18_22-28-49-lagoon-annotated.jpg" class="kg-image"/></figure><p>The Trifid Nebula is known for being a great illustration of the 3 types of nebulae. The blue area is 'reflection nebula' where it's light comes from dust that is illuminated by the stars around it. The red area is 'emission nebula' and its light is emitted by hydrogen gas rather than reflected. The dark vein-like filaments are 'dark nebula' which are simply the silhouettes of clouds of dust.</p><p>The Trifid is neither the largest or brightest nebula in the sky but I think it's contrasting features give it a unique visual appeal. Not just with regard to colour, where the red and blue collide pleasantly, but also in a luminous sense where the filaments of dark nebulosity crack the brightest part of the object like a lightning strike. It adds some drama to an object otherwise all too symmetrical and grants it its namesake: 'Trifid', derived from latin 'Trifidus' meaning 'divide into three'.</p><figure class="kg-card kg-image-card"><img src="https://res-3.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/trifid.jpg" class="kg-image"/></figure><p>The Lagoon nebula, on the other hand, is a true superstar of the night sky. It's large, bright and has it's own open star cluster nestled in the heart of it. The thick walls and ridges of colourful cloud that carve out its border envelop an interior of smooth, gently curving sheets of bright nebulosity. Small pillars and strings of dark nebula serve only to accent its features rather than distract or conceal. Closer examinations progressively pull you further and further in as new details emerge just as appealing as the last. All in all, its any easy object for anyone to appreciate its beauty.</p><figure class="kg-card kg-image-card"><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/lagoon.jpg" class="kg-image"/></figure><p>An honorable mention should go to the open star cluster M21 which is visible in the bottom left of the image. It has no relation to the other objects in the image, apart from its relative proximity to them from our perspective, and it's stars are much older than the Trifid nebula itself. </p><figure class="kg-card kg-image-card"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/M21.jpg" class="kg-image"/></figure><p>While it may seem something of a feat to have 3 messier objects in one image, we are, in fact, in a very busy part of the night sky. These objects are located in Sagittarius and near the core of the Milky Way, hence why there are so many stars in the image that seem to cohere into dusty orange objects of their own.</p><h3 id="stacking-and-linear-processing">Stacking and linear processing</h3><p>I was able to get through a much more thorough processing workflow for this image, at least compared to what I've done in the past.</p><p>Stacking was done in DSS with my usual process: Lights with kappa-sigma clipping + flats + bias. No darks this time as I'm not too sure about how consistent the temperature of my sensor is despite it's cooling apparatus. I intend to investigate more thoroughly in future but it's a tricky issue to tackle so I'm content to just dither in the meantime.</p><p>I also intend to test other stacking applications in the very near future as I'm aware DSS is getting on and doesn't deliver the best results anymore. I'm hoping to get Siril's stacking to function smoothly for me as I know it can deliver results on par with the big boys but it's also free and I already use it for the post stacking phase of my workflow anyway. I'll probably do a very unscientific comparison of stackers and publish it to this blog so keep an eye out for that.</p><figure class="kg-card kg-image-card kg-card-hascaption"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/2021-08-18T09.25.16.png" class="kg-image"><figcaption>The stacked output from DSS. Autostretched in SiriL.</figcaption></img></figure><p>Linear processing of the stacked image was done with Siril. The order of processes follows in order: Crop, Photometric colour calibration, Green noise removal, Deconvolution, asinh transform, Histogram transform, Colour saturation.</p><p>In future I'd probably skip the deconvolution step as I struggle to find any settings that don't introduce ringing artifacts in the stars. In this image I went with very mild settings where the ringing was barely noticeable but I'm pretty sure the mild effect was just exacerbated by other processes further along in the workflow. I could just be using it wrong but the tool only gives a few knobs to twiddle so the implementation might not be good. I think the problem sits squarely with it's ability to mask the stars but it doesn't give you much feedback on what it's doing on that front. Either way it did not produce any desirable effect for me even after letting the stars ring out so I'm inclined to skip on committing any degree of adjustment from it in future.</p><figure class="kg-card kg-image-card kg-card-hascaption"><img src="https://res-4.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/2021-08-18_21-21-07deconringing.jpg" class="kg-image"><figcaption>The blue fringing around the edge of these stars I believe is a direct result of decon ringing earlier in the workflow.</figcaption></img></figure><p>Another process I don't like in Siril and one I actually <em>did</em> skip was Background extraction. The tool seems simple enough to use but for whatever reason I can't get good results with it. Maybe it's an issue with my flats or something but it always seems to shift the background glow to different parts of the image rather than extracting it. Fortunately my skies are dark anyway and I don't have to contend with any strong gradients from street lights or anything like that. Ultimately I prefer to skip this step as I feel my backgrounds are more balanced without the process. </p><p>Also note that while the background in my image is relatively bright, that's mainly by choice. There is a lot of faint dust floating around in this patch of the sky and I didn't want to darken the background as much as I normally would at the risk of crushing those details.</p><p>One last thing worth mentioning is that SiriL does have a feature that can extract the background from every individual sub during the stacking process. Conceptually this could be something very powerful as most gradient sources tend to move relative to the camera perspective over an imaging session (think of how the angle of light from a street lamp will change as your telescope tracks across the sky through the evening). Again, that doesn't apply to me so much but it may end up producing better results than the regular tool does, just for extracting regular sky glow.</p><figure class="kg-card kg-image-card kg-card-hascaption"><img src="https://res-4.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/backgroundextraction.png" class="kg-image"><figcaption>Before and after background extraction. The background becomes deeper in the center and around the Lagoon but the left side background appears notably more washed out.</figcaption></img></figure><p>One SiriL process that I do love though and will never skip is 'Photometric Colour Calibration'. It plate solves your image and applies colour information according to its location in the sky. When it works, it consistently delivers a result I'm always pleased with, and I say 'when it works' because sometimes, maybe say 20% of the time in my experience, the plate solve will fail for no apparent reason. Fortunately it also provides a pretty good tool for more traditional calibration although sometimes it feels like I can only ever get the balance 98% right and that last mile is always out of reach. This is an issue I have with regular calibration in general though, not just with SiriL. That's the main reason I love the Photometric option so much - it just always feels spot on.</p><p>Another SiriL process that I love is the 'asinh transformation'. This performs the same function as a histogram stretch but it respects the original RGB ratios of your pixels. More plainly it will preserve colour as you stretch the histogram and avoid washing out the highlights like it would with the regular histogram transform tool - all without touching saturation. One practical effect of this that I really appreciate is that it really maintains the colour of your stars which can add another dimension to images. It is easy to go overboard however. In this image the starfield is so dense that it produced thick clumps of brown and orange that looked like dust and dirt scattered over it. I tried to mitigate this by doing some of the stretch with the regular histogram transform tool but I also had to dip into the Saturation tool and desaturate Orange-Brown/Yellow to really get it under control.</p><figure class="kg-card kg-image-card kg-card-hascaption"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/asinhbrown.jpg" class="kg-image"><figcaption>Dense starfields can become cheeto dust</figcaption></img></figure><h3 id="non-linear-processing">Non-linear processing</h3><p>The post linear editing phase has been a weakness of mine as it's been a slog to try out the various applications available, let alone settle on one. There's a lot of initial learning you need to do up front just to get a proper impression. As a result I've been doing as much non-linear stuff as I can in SiriL, then just doing minor touch ups in Affinity Photo, which has emerged as my preferred option from the Photoshop/GIMP/Affinity trinity (I'll write more on why in another post). For this image, the adjustments in Affinity we're mostly just limited to further tweaking of curves and levels for a bit more contrast and vibrancy. There real star of the show though, has been my first attempt at a proper star reduction.</p><p>One issue I always struggle with is stars dominating the image and distracting from deep sky subjects. It's a common occurrence in busy parts of the sky but it also tends to get exacerbated by further processing like when stretching the histogram and adjusting curves. Editing suites like Affinity really come to the rescue here as you can use their advanced selection tools (the absence of which really hampers SiriL as a complete astro processor imo) to isolate different parts of the image and, in this case, effectively generate a star mask. Affinity in particular is very easy to use for this as it allows you to select the highlights and grow/feather very responsively to get the selection smooth and accurate. </p><p>The actual weapon of choice for the reduction is the 'Minimum blur' filter. It's easy enough to shift it up and down and observe the results in real time which is much more pleasant than using Photoshops preview. I do get some issues making subpixel size adjustments as sometimes it appears to do nothing, then the same size adjustment at a different level will appear to do a lot. It's still granular enough that you will find the level you're looking for though. </p><p>The results aren't perfect - up close scrutiny will reveal smudginess around stars - but it certainly achieves the desired effect at the macro scale. At some point I'll start looking at Starnet as I expect it'll deliver cleaner results but for now I'm very happy to have added a technique to the arsenal that I consider fairly necessary for most DSO's if they're in an even remotely busy part of the sky.</p><figure class="kg-card kg-image-card kg-card-hascaption"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/2021-08-20_16-41-12star-reduction.jpg" class="kg-image"><figcaption>Spot the difference. Takes the angst out of the background but still lets the clusters shine.</figcaption></img></figure><h3 id="until-next-time-clear-skies-">Until next time... Clear Skies!</h3>]]></content:encoded></item><item><title><![CDATA[Catching up]]></title><description><![CDATA[Well it's been some time since this blog was updated. Years in fact. I've been
inactive on the astro front for most of that time due to stiction issues with a
mount that I was never able to resolve. Unfortunate, but it happens in this
field when you try to make do on a budget.

In January last year I decided to bite the bullet and get a brand new Skywatcher
EQ6-R mount so I could get back on the horse. As you can imagine the pandemic
threw that through a loop shortly after and I didn't end up re]]></description><link>https://astronewb.herokuapp.com/catch-up/</link><guid isPermaLink="false">Ghost__Post__60949a73cab915001c7c4f34</guid><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Mon, 17 May 2021 07:16:00 GMT</pubDate><content:encoded><![CDATA[<p>Well it's been some time since this blog was updated. Years in fact. I've been inactive on the astro front for most of that time due to stiction issues with a mount that I was never able to resolve. Unfortunate, but it happens in this field when you try to make do on a budget.</p><p>In January last year I decided to bite the bullet and get a brand new Skywatcher EQ6-R mount so I could get back on the horse. As you can imagine the pandemic threw that through a loop shortly after and I didn't end up receiving the mount until about 9 months later due to supply and shipping issues. I wasn't too upset though, in the grand scheme of things what's a few more months when it's already been years, especially given the circumstances.</p><figure class="kg-card kg-image-card kg-card-hascaption"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG2093.jpg" class="kg-image"><figcaption>The new mount</figcaption></img></figure><p>It took a bit more time to adapt my pier and observatory to accommodate the new mount. Instead of getting a pier plate I elected to use the mounts tripod head. I'm not sure why more people don't do this as it does save a penny. I had to lathe the central tripod head bolt and buffer it with washers to secure it to my existing plate/platform but this cost is minimal compared to that of a custom plate. Potentially there could be issues with rotation in the azimuth, especially if you bump it, but I've never had it be a problem. Once the mount was in place everything worked pretty much perfectly.</p><figure class="kg-card kg-gallery-card kg-width-wide kg-card-hascaption"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1960.jpg" width="5376" height="3024"/></div><div class="kg-gallery-image"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1959.jpg" width="3024" height="5376"/></div><div class="kg-gallery-image"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1958.jpg" width="3024" height="5376"/></div></div></div><figcaption>Looks dodgy but it works</figcaption></figure><p>Officially back on the horse and collecting deep sky photons, the learning curve started again. I learned a lot about the mechanics of mounts after my many hours invested trying to fix my previous one, but I hadn't actually spent a lot of time imaging before this point. I didn't have time to realise just how many targets you can actually image well with an unmodified DSLR before I got hit with the urge to upgrade my camera. </p><p>I spent a lot of time agonising over my potential upgrade path. Whether to modify my 600D myself, ship it overseas and pay someone else to do it, buy another modified DSLR so I could keep using my 600D as a terrestrial cam, or just buy a dedicated astro cam (mono or colour?). The latter options are ideal but too expensive, the former options less so but their value proposition was greatly diminished by the fact I'd be spending a lot on overseas shipping/tax due to the non-existent availability of modification services in my part of the world and the tiny second hand market.</p><figure class="kg-card kg-gallery-card kg-width-wide kg-card-hascaption"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-3.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/astrocam.jpg" width="842" height="613"/></div><div class="kg-gallery-image"><img src="https://res-3.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/dslr.jpg" width="2160" height="1906"/></div></div></div><figcaption>Dedicated astrocam vs DSLR</figcaption></figure><p>As luck would have it, an ideal candidate emerged in the form of an astromodified Canon 600D. It popped up on the American second hand market for about $350USD which was a reasonable price for a modified version of that model. What really made it a great value offer though, making up for the GST and shipping costs, was the addition of a cold finger peltier thermoelectric cooling mod. The lack of cooling for DSLR's is their main disadvantage over dedicated astro cams and modding them is also tricky to do <em>well</em> so to get one for a decent price was an exciting proposition.</p><figure class="kg-card kg-gallery-card kg-width-wide"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-3.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/classifieds-266501-0-03681000-1610909824.jpg" width="900" height="1200"/></div><div class="kg-gallery-image"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/classifieds-266501-0-07506600-1610909847.jpg" width="1600" height="1200"/></div><div class="kg-gallery-image"><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/classifieds-266501-0-67829300-1610909840.jpg" width="1600" height="1200"/></div></div></div></figure><p>The cooler interfaces with the camera via an aluminium cold finger which routes from the sensors steel cage to the aft exterior of the camera as can be seen in the picture above. The foil and tape help seal off any air exchange with the interior to prevent buildup of moisture and condensation. The controller is an arduino board which allows setpoint cooling in 5c increments up to -20c but the fan can only manage up to about -15c from ambient as it's been selected for low vibration rather than power. This is sufficient though as the main benefit is the setpoint cooling which allows for the building of a reusable dark library, rather than just maximum thermal noise reduction on a individual sub basis.</p><p>In practice the camera works well even if it isn't everything I hoped for. The IR spectrum sensitivity is much improved over my unmodded 600D, as expected. The cooling is a bit more of a mixed bag as it doesn't seem to be as 'setpoint' as I hoped. The temperatures reported by the camera via EXIF aren't actually close to the setpoint on the controller and also aren't that consistent even if they are definitely a bit lower when the cooler is on. It's hard to gauge though as temperatures reported by Canon cameras via EXIF are apparently taken at the digic processor rather than the image sensor. Similarly, the temperature sensor for the cooler controller is in the cold block, which is fine, but while it lets us know the blocks temperature is consistent, it doesn't necessarily give us a reliable picture of how that's translating to the sensor. All I know is that my darks taken at 10c setpoint aren't always showing similar noise patterns. Especially those that we're taken during the day vs those taken at night, even at the same setpoint.</p><p>Ultimately though, my results are very good and relatively low noise by DSLR standards, even with only modest integration times (~1hr). I credit this to the increased signal gain of the IR filter mod, very dark skies and the magic of dithering, which I now have functioning smoothly.</p><figure class="kg-card kg-gallery-card kg-width-wide kg-card-hascaption"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/18-s17cnoise.png" width="1181" height="784"/></div><div class="kg-gallery-image"><img src="https://res-3.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/180s20cnoise.png" width="1176" height="781"/></div></div></div><figcaption>Two dark frames taken at 10c setpoint with an EXIF of about 20c (resized/resampled and very compressed though)</figcaption></figure><p>My final addition to the setup is a second scope! While I very much enjoy the results from my ED80T-CF, as my only scope it does leave me quite limited in my ability to capture and enjoy smaller objects like galaxies and such. I've had eyes on a Newtonian to give me a bit more reach and at a modest price but the tradeoff is having to deal with mechanical issues. By chance (again) another ideal candidate revealed it on the second hand market, albeit more locally this time. It's an 8" F4 Skywatcher Newt that the previous owner has modified to shore up the mechanical issues that generally plague these scopes such as the dodgy collimation screws and springs.</p><figure class="kg-card kg-gallery-card kg-width-wide kg-card-hascaption"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-4.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/1526201938.jpg" width="1152" height="1536"/></div><div class="kg-gallery-image"><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/1526201949.jpg" width="2048" height="1536"/></div><div class="kg-gallery-image"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/1526201960.jpg" width="2048" height="1536"/></div></div></div><figcaption>Modifications include primary mirror adjustment screws less prone to flex, longer springs and a printed stud to help hold the mirror in place.</figcaption></figure><p>I'm yet to give it a spin as my coma corrector is stuck at the port and I'm still busy trying to capture some wider field targets with my refractor, before I commit to all the effort of mounting a new scope and having to cook up different cable management and all that annoying stuff. My plan is to piggyback the refractor on the newt so I can easily switch between wide field and, well, wider field. I figure I can switch my cameras between the two and use each one for guiding the other. </p><figure class="kg-card kg-image-card kg-card-hascaption"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG2073.jpg" class="kg-image"><figcaption>Current setup</figcaption></img></figure><p>With so much new stuff on my plate that means more trials and tribulations. Already I have more learnings to document which I think could be helpful to others. Up next I'll probably being talking about how to make the most of free/cheap software options for stacking and processing or perhaps about my transition from APT to NINA and how they compare for DSLR users.</p><p>Until then.. Clear skies!</p>]]></content:encoded></item><item><title><![CDATA[Shutter shock]]></title><description><![CDATA[I've been largely happy with my NexDome since setting it up at the start of this
year. It's not perfect but all the issues it can present are generally quite
manageable and at the end of the day it sells at a price point that can't be
beat. One of said issues is securing it against wind. I only have the dome part
of the NexDome rather than the full observatory so can't make use of their wind
lock. Instead my own solution has been to tie it down to the observatory
structure using multiple coiled ]]></description><link>https://astronewb.herokuapp.com/shutter-blown-away/</link><guid isPermaLink="false">Ghost__Post__6029194dcf34a2001cc2de21</guid><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Tue, 23 Jul 2019 22:32:00 GMT</pubDate><content:encoded><![CDATA[<p>I've been largely happy with my NexDome since setting it up at the start of this year. It's not perfect but all the issues it can present are generally quite manageable and at the end of the day it sells at a price point that can't be beat. One of said issues is securing it against wind. I only have the dome part of the NexDome rather than the full observatory so can't make use of their wind lock. Instead my own solution has been to tie it down to the observatory structure using multiple coiled springs spread out around the dome ring. It's probably massive overkill but when it comes to a shiny new expensive dome, the peace of mind is priceless. At least it was until one morning a few weeks back when the shutter on my NexDome was blown out clean by high winds! Peace, it would seem, never lasts.</p><figure class="kg-card kg-image-card"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1333.jpg" class="kg-image"/></figure><p/><p>I was just lucky that it happened in the morning when I was awake so I actually heard a loud bang coming from the observatory vicinity and was able to get out there and take my gear down before it all got soaked. I didn't see what happened but it looks like the wind managed to push the front panel of the shutter up a bit then once it was under, the additional lift pushed the whole shutter all the way up and out.</p><figure class="kg-card kg-gallery-card kg-width-wide"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1531.jpg" width="3024" height="5376"/></div><div class="kg-gallery-image"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1532.jpg" width="5376" height="3024"/></div></div></div></figure><p>It's suffered a lot of cracking at the rear which I've glued and taped back up as best I can. I didn't stop to take pictures beforehand unfortunately as I was busy trying to fix it up while the rain was coming in 😂 My dome is about 5m above ground so my initial thought was that the damage was done when the shutter hit the ground but one of the rear backstops (that sits against the wheels when closed) also snapped off. Both instances of damage are at opposite ends of the shutter so are unlikely to both be the result of the same impact. I found the backstop fragment on the ground some ways from where the shutter landed so I'm thinking that the shutter got hooked at the backstop and the wind just buffeted it with enough force that it pivoted up and generated enough strain to snap the backstop before the shutter blew away entirely.</p><figure class="kg-card kg-gallery-card kg-width-wide"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1534.jpg" width="5376" height="3024"/></div><div class="kg-gallery-image"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1538.jpg" width="3024" height="5376"/></div></div></div></figure><p>I've now secured the front of my shutter with it's own spring tiedowns which should stop the wind ever lifting it again. Let this be a word of warning to other NexDome owners though: secure your shutter. It seems like an obvious step in hindsight but it's an easy thing to overlook. Even with the wind lock in the full NexDome observatory package it only secures the dome but not the shutter itself. I've heard they're now including guards in new orders that sit inside the shutter channel at the top of the dome to prevent it from lifting out. This is definitely helpful and would stop you from loosing your shutter entirely but wouldn't protect against the front lifting and maybe letting a bit of moisture in. If you have the motorized shutter kit I suspect that'd provide a useful bit of resistance to this as well and is probably why shutters getting blown out isn't more common but it's not true protection. </p><p>At the end of the day it only takes one incident to put your gear at risk. I was lucky mine didn't occur during the night as the winds were just as high. If it did, everything would've got soaked. Gusts around that period were up around 70-80kmph which is windy obviously but not exactly a hurricane. Even if your dome has withstood strong winds before, a slightly different wind direction the next time around could push it over the edge. Whatever it takes just find a way to secure your shutter. It'll be worth it.</p>]]></content:encoded></item><item><title><![CDATA[Cable Crisis: How to make your own DB9-RJ12 cable for Synscan Handcontrollers]]></title><description><![CDATA[After finishing the observatory and starting to shift my scope and gear into it,
I very quickly found that all my essential cables were not where I thought they
were... USB cables for my cameras, rj12 to db9 and usb to serial cables for
connecting the handcontroller to my laptop, even the RA and Dec motor cables
essential to control the mount - all missing. After turning the house upside
down searching for them without result, I've had no choice but to replace them.
The usb cables are no trouble]]></description><link>https://astronewb.herokuapp.com/cable-crisis/</link><guid isPermaLink="false">Ghost__Post__6029194dcf34a2001cc2de20</guid><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Tue, 12 Mar 2019 05:09:05 GMT</pubDate><content:encoded><![CDATA[<p>After finishing the observatory and starting to shift my scope and gear into it, I very quickly found that all my essential cables were not where I thought they were... USB cables for my cameras, rj12 to db9 and usb to serial cables for connecting the handcontroller to my laptop, even the RA and Dec motor cables essential to control the mount - all missing. After turning the house upside down searching for them without result, I've had no choice but to replace them. The usb cables are no trouble in this regard, they are standard types which can be bought wherever, but the motor cables and the db9-rj12 cable are proprietary and much more difficult to replace.</p><figure class="kg-card kg-gallery-card kg-width-wide kg-card-hascaption"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/motor-cables.jpg" width="800" height="533"/></div></div></div><figcaption>Mount motor cables</figcaption></figure><p>The RA motor cables for my mount don't appear to be available for purchase anywhere online, not even from Orion themselves. The official Orion website would have you believe you can only get them by ordering a whole new motor upgrade kit for the Skyview Pro. At the cost of several hundred dollars though, it's obviously not a good option just to get some cables.</p><p>Contacting Orion directly they seemed to indicate that they could supply replacements but refused to entertain me further until I could provide proof of purchase for my mount, which I no longer have. This is usually how all my interactions go with Orion unfortunately. Instead I got in contact with my local Orion supplier who confirmed that there is, in fact, a spare parts catalog from which these cables could be ordered. It cost me $40 NZD in the end, which I think is a bit steep for cables, but ultimately I didn't have much choice. It's this seething resentment of overpriced cables though that would lead me down the DIY path for my next cable.</p><figure class="kg-card kg-image-card"><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/rj12-to-serial-cable-1.jpg" class="kg-image"/></figure><p>The normal way to connect a pc to a mount is via the handcontroller. If the controller is new enough it will have a usb port which makes things easy. If it's a bit older it will have a rj12 port and an rj12-to-serial (RS232) cable to go with it. Of course not many laptops and PC's have serial ports these days but you can just use a serial-to-usb adapter to complete the connection instead. This latter method is the one I have to use but there is a third option, albeit an unofficial one.</p><p>This third option is a usb cable that can connect direct from a usb port on the pc to the rj45 port on the mount that the handcontroller normally connects to. This method, known as EQDirect, allows you to bypass the handcontroller completely, meaning less cables and adapters to get in the way and less potential comms issues.</p><p>As someone missing all his cables, I'm left with 2 options. A) Replace the rj12 to serial cable and get a usb to serial adapter, or B) Just go straight for an EQDirect cable. The latter option is a $70NZD purchase and the former is, well, a bit of a lottery to even find a cable that will work. The problem is that, much like the motor cables, there's no rj12 to serial replacement cable readily available for my mount. Even though you can find cables with the same plugs/connectors out there (such cables are used in point of sale devices and what not), there's no guarantee it will be compatible with my mount as the pinout to the serial port could be completely different.</p><p>Being a cheapskate, the only thing that makes sense at this point is to make my own cable - but which one? EQDirect or RJ12 to serial? EQDirect is a superior connection method and isn't anymore costly to put together, in fact, it's probably cheaper as you don't need to get a usb to serial adapter to use it, but there is one caveat: it's a little bit dangerous. You can potentially zap your mount if you make a mistake and end up routing some volts to the wrong pin or there's a short. It's a minor threat but a threat nonetheless. I believe using such a cable may also have warranty implications as well. In the end, I decided to make up an rj12 to serial because of this. I'd like to get some actual astro done before I risk frying my gear. I probably will put together an EQDirect at some point in the future though. I may make a guide for it but there's already a bit of material out there on this (get started <a href="http://eq-mod.sourceforge.net/eqdirect2.htm">here</a><a> </a>if that's what you're looking for).</p><figure class="kg-card kg-gallery-card kg-width-wide kg-card-hascaption"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/rj12.jpg" width="1000" height="1000"/></div><div class="kg-gallery-image"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/db9-serial-to-terminal.png" width="775" height="667"/></div></div></div><figcaption>DB9 RS232 Serial to terminal adapter (right) RJ12 cable (left)</figcaption></figure><p>To get this done, all you need is an RJ12 cable and a DB9 RS232 adapter that will let you terminate your own pinout. A suitable cable stripper would make the job easier and a screwdriver will be required if your adapter has screwdown terminals.</p><p>In my case I used the exact style of adapter pictured above but I've seen other types such as ones with gator clips instead of screwdown terminals. Any style will work as long as it's RS232 and you are clearly able to identify which pins its terminals map to. <a href="https://www.ebay.com/itm/1PCS-DB9-Male-Adapter-Signals-Terminal-Module-RS232-Serial-to-Terminal-DB9-S/302266950730">This</a> $1 adapter on ebay will do the job just fine. Also make sure that the plug gender for the adapter will pair with whatever gender your usb to serial adapter is so they can actually connect. I overlooked this detail so had to use a gender changer. It's not a big deal to do this but it's better to avoid the problem if you can. I've heard that gender changers sometimes don't have all the pins connected which can only lead to a lot of frustration...</p><p>As for the RJ12 cable, you may think you've got a bunch of this stuff laying around spare somewhere from old phones or networking gear but chances are you don't have the right stuff. That's because you need a 6p6c cable which means it has 6 wires inside it all crimped into the 6 positions and contacts on the plug. Most of the stuff you have laying around will only have 2 wires which is not suitable. A 4 wire 4p4c cable would probably work but that's not what I used. Fortunately this stuff is still pretty cheap so just buy some if you have to.</p><figure class="kg-card kg-image-card"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/synscan_db9_pinout.jpg" class="kg-image"/></figure><p>To get started just cut one end of the RJ12 cable and strip a couple inches back to the wires. As can be seen in the diagram above, you only need to use 3 of the wires, the rest can be cut back so they're not in the way and can't short on each other. Why does Orion use rj12 when they only need 3 wires? No idea. Maybe just a consequence of whatever I/O happened to be present on their controller board? Anyway, strip the wires were actually going to use back to the copper and screw them down into the corresponding terminals according to the diagram. The colour of the wires will vary depending on the cable but just look at the bottom of the connector to see which colour is in which position. As long as the wire in position 2 terminates to pin 2, position 3 terminates to pin 5 &amp; position 5 terminates to pin 3, then your cable should be good to go.</p><figure class="kg-card kg-image-card"><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1375.jpg" class="kg-image"/></figure><p>Also, when getting a serial to usb adapter, there appear to be 2 main chipsets that you will encounter: one from Prolific and the other from FTDI. I've used both types successfully but I've read in a lot of sources that the FTDI is superior and less prone to comms issues so I'd say make the effort to acquire one with their chip if you can. They seem to cost the same amount regardless.</p><figure class="kg-card kg-image-card"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1378.jpg" class="kg-image"/></figure><p>If you want to keep it tidy you can get clip together casing to contain and protect the db9 adapter and cable. For me though, I've just taped the whole thing to my pier so that the cable isn't hanging down and pulling on the wire terminals.</p><figure class="kg-card kg-image-card"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/adapter-taped.png" class="kg-image"/></figure><p>I've been using this cable with no issues for a few weeks now so I think it's safe to say the pinout above is good. I've been able to get some observing done but I'm still dealing with some longstanding autoguiding problems on my mount.  I believe the issues all come down to stiction (and to some degree, backlash) internal to my mount that maybe I can't do much about but I will still document the issue and seek help. This will likely be my next entry but until then... clear skies.</p>]]></content:encoded></item><item><title><![CDATA[Final prep for Dome & Observatory]]></title><description><![CDATA[With the dome finally in place, the hard part of the project was complete.
Getting the observatory to a usable state still required a little more work
though. First up was the weatherproofing.

The NexDome is one of the cheapest astro domes out there but like everything in
astro, it's not actually 'cheap'. That's why the first instinct after installing
the damn thing is to make sure it isn't gonna blow away. When assembling the
dome I made sure to secure a few flat metal braces (although I did n]]></description><link>https://astronewb.herokuapp.com/final-prep-for-dome-observatory/</link><guid isPermaLink="false">Ghost__Post__6029194dcf34a2001cc2de1f</guid><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Mon, 21 Jan 2019 10:43:38 GMT</pubDate><content:encoded><![CDATA[<p>With the dome finally in place, the hard part of the project was complete. Getting the observatory to a usable state still required a little more work though. First up was the weatherproofing.</p><figure class="kg-card kg-gallery-card kg-width-wide"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1332.jpg" width="3024" height="5376"/></div><div class="kg-gallery-image"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1333.jpg" width="3024" height="5376"/></div></div></div></figure><p>The NexDome is one of the cheapest astro domes out there but like everything in astro, it's not actually 'cheap'. That's why the first instinct after installing the damn thing is to make sure it isn't gonna blow away. When assembling the dome I made sure to secure a few flat metal braces (although I did need to bend them a bit to fit the shape of the wall - see above images) under the interior nuts on the lower walls so I could tie it down with something later. After humming and hah'ing over what material to tie it down with we settled on these springs. They're easy to connect/disconnect and provide a lot of force while still having a bit of give in them. Overall I think it's a good solution. I've got 4 in place around the dome which is probably overkill but I don't have to hook them all up if I don't feel like it. The NexDome is supposed to be able to handle some high winds just sitting freely on its own but knowing that it's tied down makes me a bit less anxious when the winds kick up.</p><figure class="kg-card kg-gallery-card kg-width-wide"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1340.jpg" width="5376" height="3024"/></div><div class="kg-gallery-image"><img src="https://res-3.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1341.jpg" width="5376" height="3024"/></div></div></div></figure><p>The bottom of the dome ring has a few gaps where the base of its segments interlock. It's possible water could blow underneath in sufficiently high winds so we applied a bit of sealant to these locations.</p><figure class="kg-card kg-gallery-card kg-width-wide kg-card-hascaption"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1342.jpg" width="5376" height="3024"/></div><div class="kg-gallery-image"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1344.jpg" width="5376" height="3024"/></div></div></div><figcaption>See the black material stapled under the base of the dome</figcaption></figure><p>The sealant would only stop water coming into the interior though. It's still possible water could blow under the dome ring then sit on the wooden ring which wouldn't be ideal. To prevent this we stapled some waterproof foam material to the edge of the wooden ring then pulled it up as far as we could between the bottom of the dome and the ring. It doesn't interfere with the motion of the dome and will serve it's purpose although I'm not sure how long the material will last. For now I'm just happy to see how it goes and deal with it in the future if it starts to wear out.</p><figure class="kg-card kg-gallery-card kg-width-wide"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1335.jpg" width="5376" height="3024"/></div><div class="kg-gallery-image"><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1336.jpg" width="5376" height="3024"/></div><div class="kg-gallery-image"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1338.jpg" width="5376" height="3024"/></div></div></div></figure><p>I was eager to get the pier into place and finally see how stable it would be once secured into place. The countersinks in the bottom plate are not flat so I've used some metal plates to give the nuts a better contact area. You can see from the curving of the plates that I've got them pretty damn tight. It took a bit of time but it's level at the bottom too. In future I might fill in the area below the bottom plate to add more stability. Not sure with what material though - maybe more concrete? Will see how it goes for now though.</p><figure class="kg-card kg-image-card"><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1313.jpg" class="kg-image"/></figure><p>It's a very tall pier so I've always been a bit concerned with how it would turn out but after initial installation I'm happy with how sturdy it feels. With the weight of my mount on top it does get a small wobble/vibration when bumped though. The pillar is isolated from the rest of the structure so I'm just hoping and praying that everything will be fine as long as I don't bump it while it's in use! The viability of this structure as an observatory really will come down to whether the pillar and pier fulfill their role effectively. This factor does weigh on my mind a bit and it won't be dispelled until I can finally do some guided astrophotography.</p><figure class="kg-card kg-gallery-card kg-width-wide kg-card-hascaption"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-3.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1311.jpg" width="3024" height="5376"/></div><div class="kg-gallery-image"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1312.jpg" width="3024" height="5376"/></div></div></div><figcaption>Nice n level</figcaption></figure><p>I don't actually have a pier adapter plate for my mount so I'm just using the the top of it's tripod. It's not secured to the pier top plate beyond the central rod that's screwed in pretty snugly so it could potentially rotate but not without the application of at least a little force (like from an inadvertent bump). After the initial polar alignment I will be rechecking it semi regularly just to be sure it's not moving somehow.</p><figure class="kg-card kg-image-card"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1343.jpg" class="kg-image"/></figure><p>Not sure where to fix the hand controller and junction box but this will do for now. Turns out the tripod leg leaves them at a height which is comfortable to use. I'm also realising now that cable management will be awkward with such a tall pier so I'm still thinking about how I'm going to lay everything out.</p><figure class="kg-card kg-image-card"><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1334.jpg" class="kg-image"/></figure><p>One of the issues I found with the Nexdome is that the shutter can be very difficult to open and close. This is because the lower shutter has to squeeze between the upper shutter and the rear wall panel to fully open and there's no mechanism to mitigate the friction. A liberal application of silicone at the edges went a long way to alleviating this problem although it does mean a bit of shit gets dragged in from the exterior when I close the shutter (as can be seen in the image above). Another issue I've found with the shutter is that it's exterior gutter provides nowhere for water to drain away. This mean a bit of moisture builds up and will drip down as you open it, likely onto your scope and mount. It's not a big deal, and for now I'm content to just wipe it away when opening the shutter, but it is a bit of a flaw in the design. As for a good permanent solution I'm not sure what to do. You couldn't drill any drainage holes as it would just drain into the interior. Maybe it would be best to fill it with something? Or just chuck some sponge in there to absorb it so it doesn't drip? A minor issue for another day...</p><figure class="kg-card kg-gallery-card kg-width-wide"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1347.jpg" width="3024" height="5376"/></div><div class="kg-gallery-image"><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1350.jpg" width="3024" height="5376"/></div></div></div></figure><p>The last obstacle in the way of a finally usable observatory was actually being able to reach up and close the bloody shutter. There's quite a bit of distance from the central platform to the top of the dome and while I can open the shutter from standing position, it's too high to reach when it's fully open. Standing atop a step ladder is somewhat dodgy when your already elevated on a small platform, with no rails for safety, and you need a bit of leverage from somewhere because the shutter is providing some resistance. A fixed ladder was needed and 6 meters of H1 framing timber later, that's what I had. I elected for a straight up and down ladder as opposed to an angled one just to minimize its footprint on the platforms already limited floor area. It's only got 4 rungs as that's all I really need to get high enough to reach the shutter at full extension. The rung at the very top is to provide me a bit of leverage to pull against as the shutter does have a bit of initial resistance when closing and the handle on it is unfortunately a bit flimsy.</p><figure class="kg-card kg-gallery-card kg-width-wide"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1346.jpg" width="5376" height="3024"/></div><div class="kg-gallery-image"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1348.jpg" width="5376" height="3024"/></div></div></div></figure><p>So with the ladder done I basically had everything needed to start using the observatory! On the next clear evening I could bring out my telescope, laptop, camera, plug it all in and start dialing in my permanent polar alignment. It was under this halo of great anticipation that I would come to discover that my mounts motor cables were missing! These cables are critical to get any functionality from the motor so I simply can not do anything until they are found or replaced. Unfortunately they are not only proprietary but also unique to my particular model of mount which is now quite a few years old. It doesn't seem like you can get these easily and the manufacturer (Orion) doesn't list them anywhere on their site outside of being included with a whole new mount or GOTO upgrade kit. I emailed them about it but got no response... Fortunately their NZ dealer might be able to get me some replacements from another mount that's being returned (hopefully nothing possibly related to the cables...) and I should get a confirmation of that some time this week. My rs232-to-rj11 and usb-to-serial converter cables have also gone missing with the motor cables but they are much easier to get replacements for at least. It's annoying to have to fork up for these overpriced cables but after turning over the whole house looking for them I don't have much choice. Such is life!</p>]]></content:encoded></item><item><title><![CDATA[NexDome online]]></title><description><![CDATA[After returning from a 3 month hiatus in Australia to a spell of fine weather,
the Dome is finally up and in place. There's still a little bit to be done
before the observatory will be fully functional but the hard part is done. It
certainly wasn't without it's challenges though and there may be a few more to
come.

The final resultThe first step was removing the temporary plywood roof. To our
bemusement we found the boards wouldn't budge even after unscrewing them. Turns
out some of the sealant]]></description><link>https://astronewb.herokuapp.com/dome-online/</link><guid isPermaLink="false">Ghost__Post__6029194dcf34a2001cc2de1e</guid><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Mon, 07 Jan 2019 07:22:03 GMT</pubDate><content:encoded><![CDATA[<p>After returning from a 3 month hiatus in Australia to a spell of fine weather, the Dome is finally up and in place. There's still a little bit to be done before the observatory will be fully functional but the hard part is done. It certainly wasn't without it's challenges though and there may be a few more to come.</p><figure class="kg-card kg-image-card kg-card-hascaption"><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1309.jpg" class="kg-image"><figcaption>The final result</figcaption></img></figure><p>The first step was removing the temporary plywood roof. To our bemusement we found the boards wouldn't budge even after unscrewing them. Turns out some of the sealant we'd used for waterproofing was of the adhesive variety so we had to bash the thing open. We were off to a great start.</p><p>With the roof open, our next objective was to fix some more timber around the opening to build out a bigger platform to attach our wooden ring to. We'd already prepared the timber some months back so we just need to trim it a little bit to fit then nail it in. This ring would serve as a platform to sit the dome on.</p><figure class="kg-card kg-gallery-card kg-width-wide kg-card-hascaption"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-3.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1290.jpg" width="5376" height="3024"/></div><div class="kg-gallery-image"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1295.jpg" width="5376" height="3024"/></div><div class="kg-gallery-image"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1296.jpg" width="3024" height="5376"/></div></div></div><figcaption>The grey boards are the additions that the ring will sit on</figcaption></figure><p>It took more time than expect to trim the boards up but the end result was pretty good. We hauled the ring up with ropes and fixed it with screws after centering it relative to the pier.</p><figure class="kg-card kg-image-card kg-card-hascaption"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1298.jpg" class="kg-image"><figcaption>The dome ring will not sit on our hexagonal opening thus we had to create our own ring platform</figcaption></img></figure><p>We eagerly proceeded to get the dome ring into place to see how well it would fit. It was a bit tight with some of the outer screw holes sitting very close to the edge of the platform but it would have to do. </p><p>At this point we were also faced with the conundrum of whether or not we should screw the dome ring down before hauling up the dome itself so we could be sure the shape of the ring would fit the dome alright. The latter would've been ideal but the nature of our structure meant that once the dome went up it would have to go straight into place. The roof is too steep to stand on so we can't manipulate the dome from the outside nor sit it anywhere while we make adjustments. In the end we elected to screw it down and just hope for the best.</p><figure class="kg-card kg-image-card"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1299.jpg" class="kg-image"/></figure><p>With the dome ring in place, assembly of the Nexdome itself began. It comes in about a dozen pieces which all need to be slotted and bolted together. Like any sort of flat pack assembly, it seems simply enough in theory but in practice it's always more difficult than anticipated. The included instructions were very minimalist and even had some minor errors which didn't aid the process. Further to that, the provided collection of nuts/bolts/screws was a total mess. There was a vast excess of washers but not enough bolts forcing me to go out and buy some more from the hardware store. Not a major but definitely annoying when you've forked up so much money for the product in the first place. </p><figure class="kg-card kg-gallery-card kg-width-wide kg-card-hascaption"><div class="kg-gallery-container"><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1283.jpg" width="5376" height="3024"/></div><div class="kg-gallery-image"><img src="https://res-4.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1284.jpg" width="3024" height="5376"/></div></div><div class="kg-gallery-row"><div class="kg-gallery-image"><img src="https://res-4.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1288.jpg" width="5376" height="3024"/></div><div class="kg-gallery-image"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1300.jpg" width="5376" height="3024"/></div></div></div><figcaption>Being a dome, none of it's parts are flat or square so nothing will sit nicely where it's supposed to. It's a two man job really but I managed to get by using a web of timber offcuts to prop things up.</figcaption></figure><p>My concern with this sort of thing is always that some holes won't line up for the bolt/screws/nails and of course this case was no exception. Most of the time and effort of assembly was spent trying to contort the pieces in to place in order to get the bolts in. Fortunately there was no need to drill anything in the end and it all came together. With the dome assembled, the next step would be the my most dreaded, and ultimately, the most challenging part of the entire process: getting the damn thing on the roof.</p><figure class="kg-card kg-image-card kg-card-hascaption"><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1302.jpg" class="kg-image"><figcaption>We clamped some boards to the roof to provide a bit of buffer so the dome could slide over bolts.</figcaption></img></figure><p>The challenge presented by the dome is a matter of getting a large, bulky and fragile object, from the ground, on to a roof 3 meters up from it. It has over 2 meters diameter, weighs over 50kg and when you lift it at an angle, it feels like the joints could buckle at any moment. The initial plan of just tipping it up on its end and pushing it on to the roof very quickly became an obviously bad idea. It is just too bulky and heavy to lift at such an extreme angle and would probably buckle as well. We needed some leverage so we could lift it up at a more forgiving angle. Unfortunately the deck around the structure is shorter than the diameter of the dome which means getting in behind it at a flatter angle would be really awkward as well as risky due to there being a bit of a drop off from the deck. </p><figure class="kg-card kg-image-card kg-card-hascaption"><img src="https://res-4.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1304.jpg" class="kg-image"><figcaption>The space we were working with.</figcaption></img></figure><p>In the end we threw caution to the wind. With Dad pushing up one end of the dome from ground level and me lifting from underneath the center of the dome, while on a table perched at the very edge of the deck, we had enough leverage to get one end of the dome onto the roof and sit the other end on the table. From there we squeezed onto one end of the table each and hauled the whole thing all the way up on to the roof. It was a nightmare of maneuver in terms of safety standards but we got through it all without anyone toppling to their doom. We went into the obs and pulled it up to the ring. With a bit of prodding at the edges it seemed to fall into place. I immediately started rotating it and sure enough it was working. After one complete rotation I finally felt relief. This was always going to be the most difficult and most delicate stage of the operation and at last it was done. There was and still is a bit more work to be done before the observatory is ready for use but I'll leave it there for now.</p><figure class="kg-card kg-image-card kg-card-hascaption"><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1307.jpg" class="kg-image"><figcaption>View from the shutter</figcaption></img></figure>]]></content:encoded></item><item><title><![CDATA[Pier is ready]]></title><description><![CDATA[So the pier is now complete and I'm happy with the final result. Pretty much
everything is to specification (with the exception of one minor niggle) and it's
extremely sturdy, which is something I was concerned about initially considering
how tall it is.



It passed its first test which was to slot the base over the bolts in the
central pillar. I was a bit worried about this as we did have to force down the
wooden template a little when we put that together and with steel you don't
really get t]]></description><link>https://astronewb.herokuapp.com/pier-is-ready/</link><guid isPermaLink="false">Ghost__Post__6029194dcf34a2001cc2de1d</guid><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Thu, 30 Aug 2018 12:29:58 GMT</pubDate><content:encoded><![CDATA[<!--kg-card-begin: markdown--><p>So the pier is now complete and I'm happy with the final result. Pretty much everything is to specification (with the exception of one minor niggle) and it's extremely sturdy, which is something I was concerned about initially considering how tall it is.</p>
<p><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1214.jpg" alt="IMAG1214"/></p>
<p>It passed its first test which was to slot the base over the bolts in the central pillar. I was a bit worried about this as we did have to force down the wooden template a little when we put that together and with steel you don't really get the same room to force things. Fortunately it fits perfectly.</p>
<p><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1215.jpg" alt="IMAG1215"/></p>
<p>200mm bolts will provide a lot of leeway if I ever need to adjust height for whatever reason. If I get another mount in future it shouldn't be difficult to get the top plate to the ideal height. With the setup of the nuts it's very secure.</p>
<p><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1216.jpg" alt="Pier top"/></p>
<p>I degreased it and gave it a couple of coats of paint for rust resistance.</p>
<p><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1221.jpg" alt="IMAG1221"/></p>
<p><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1230.jpg" alt="Top plate"/></p>
<center>*Top down view of the top plate*</center>
<p><img src="https://res-3.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1232.jpg" alt="Middle plate"/></p>
<p>I will need to sand the plates a bit as the paint has blocked the bolt holes. I'll probably gently sand the top plate as well just to get it nice and smooth/even for the mount to sit on.</p>
<p><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1231.jpg" alt="Pier base"/></p>
<p>I asked for a small countersink for the bolt holes on the base as I was concerned that the bolts in the central pillar might be too short and I wouldn't be able to screw the nuts down onto the base enough. Unfortunately I didn't think to specify that I needed the countersinks flat and you can see the consequences above. Regardless, I am still able to screw the nuts down pretty tight and get the pier sturdy enough. There is some available length on the bolts as well though (see image second from top) so I think I will still get some small metal plates to sit over the countersinks and just screw down on those anyway. On such a tall pier, the contact at the base is where the rubber meets the road so to speak so I really do want to get it as secure as possible. If it takes a bump then it's going to spoil any exposure happening at the time but there is no way around that. The real test is to see if it picks up any vibrations while in use though. I don't believe this should be possible anyway as the central pillar does not make any contact with the observatory structure at any point. Will be a bit anxious till this gets proven in practice though!</p>
<p>Anyway, there's nothing to stop me going ahead and putting the dome up now so that'll be my next update. I'm not sure when that'll  happen, just waiting for a fine day without wind or rain and at the moment it seems we always get one or the other. Hopefully it should happen sometime within the next couple of weeks.</p>
<!--kg-card-end: markdown-->]]></content:encoded></item><item><title><![CDATA[Finish line in sight]]></title><description><![CDATA[After just over 1 year the observatory is finally nearing completion! All that
remains is to install the dome and pier and it will be ready for observing.



The Nexdome finally arrived many months after ordering. The box came a bit
banged up (it came all the way from Canada via Australia!) but everything inside
appears to be intact and undamaged. It seems to have come short of a few
nuts/bolts but this shouldn't pose a major obstacle even if it is a bit
annoying. The instructions are also somew]]></description><link>https://astronewb.herokuapp.com/finish-line-in-sight/</link><guid isPermaLink="false">Ghost__Post__6029194dcf34a2001cc2de1c</guid><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Sun, 19 Aug 2018 00:23:26 GMT</pubDate><content:encoded><![CDATA[<!--kg-card-begin: markdown--><p>After just over 1 year the observatory is finally nearing completion! All that remains is to install the dome and pier and it will be ready for observing.</p>
<p><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1068.jpg" alt="IMAG1068"/></p>
<p>The Nexdome finally arrived many months after ordering. The box came a bit banged up (it came all the way from Canada via Australia!) but everything inside appears to be intact and undamaged. It seems to have come short of a few nuts/bolts but this shouldn't pose a major obstacle even if it is a bit annoying. The instructions are also somewhat skint on detail but I think I've got a good grasp on how to assemble it. As long as all the bolt holes line up it will be easy but I wouldn't be surprised if I end up having to drill some new ones. The hardest part will be getting it up into position as the observatory roof is too steep to stand on. I may just assemble it up there from the inside but that will also be a bit awkward. We'll see how it goes.</p>
<p><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1205.jpg" alt="IMAG1205"/></p>
<center>*Dome parts to be assembled*</center>
<p><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1203.jpg" alt="IMAG1203"/></p>
<center>*Ring base that dome sits and rotates on*</center>
<p>The gap at the top of the roof isn't big enough to fit the dome so we've had to produce a wood ring to provide a wider platform for it to sit on. Affixing it will be a simple matter of screwing it down to the roof along the inside diameter then the dome's base ring can be screwed down along the outer. The ring provides a little bit of extra width to help center the dome with the pier. I'm not sure how important it is to do this but I want to get it as close as possible as I presume it will help with dome automation accuracy in future.</p>
<p><img src="https://res-4.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1208.jpg" alt="IMAG1208"/></p>
<center>*Dome is 2.2m diameter and will sit on the grey ring*</center>
<p>To get the dome centered though, I need to have the pier in place. After looking at the price of existing piers I figured I'd probably save a lot getting an engineer to do a custom job for me. I put together a wooden prototype pier (see image below) to help illustrate what I'm looking for. The prototype doesn't include a top plate or its bolts so you'll have to use your imagination for that.</p>
<p><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1177.jpg" alt="IMAG1177"/></p>
<center>*Pier prototype*</center>
<p>After consulting with a couple of local engineers we've decided to adjust the design to one that uses rods rather than intersecting plates. This uses less steel and should save a lot on cost while still being fit for purpose. Provided it's steady, as the engineers assure me it will be, I actually prefer this design, even over the traditional pipe. It allows access under the plates which could be useful. For the moment I don't plan to use a pier adapter plate for the mount and will just sit the cradle from the top of the mounts tripod on the top plate. Having space under the plates means I will be able to use the rod that came with the mount to secure it. With a more standard pier design this would not be possible (not that that would be a big deal anyway).</p>
<p><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/pier.jpg" alt="pier"/></p>
<p>The pier should be finished any day now and after it's done I'll be waiting for a fine day without wind to get out there and finish the job. Once the roof is off, the building is exposed to the elements so we'll need to do it all in one go. Everything going to plan I suspect it'll be only a few hours work but rarely have we not encountered unexpected challenges in this process! Next update will follow once the pier is completed.</p>
<!--kg-card-end: markdown-->]]></content:encoded></item><item><title><![CDATA[Back in action]]></title><description><![CDATA[After a long hiatus through the winter I'm back in action on the astronomy
front. We've resumed work on the observatory installing the windows and door.
Next step is to put the roof on - the Colorsteel should be here in about a week.

I plan to power the building with solar so recently I've been investigating
solutions on that front. I've already got a couple of 75w panels lined up that I
can get for free. Later this week I'll be checking out a friends off-grid home
setup and after that I'll loc]]></description><link>https://astronewb.herokuapp.com/back-in-action/</link><guid isPermaLink="false">Ghost__Post__6029194dcf34a2001cc2de1b</guid><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Thu, 30 Nov 2017 09:15:43 GMT</pubDate><content:encoded><![CDATA[<!--kg-card-begin: markdown--><p>After a long hiatus through the winter I'm back in action on the astronomy front. We've resumed work on the observatory installing the windows and door. Next step is to put the roof on - the Colorsteel should be here in about a week.</p>
<p>I plan to power the building with solar so recently I've been investigating solutions on that front. I've already got a couple of 75w panels lined up that I can get for free. Later this week I'll be checking out a friends off-grid home setup and after that I'll lock in my own design and start grabbing the hardware. It'll go in after I've done the roof.</p>
<p>The big news is that I have a dome on the way. The numbers didn't add up very well in terms of costing my own fibreglass dome so I started evaluating existing products. Options are limited at the value end of the market but there are a few products available. The biggest challenge is finding someone who can affordably ship to this part of the world as the shipping generally costs as much as, or more than, the dome itself. Unfortunately there's really no way around this issue as all homegrown dome options are in more expensive ranges. Nonetheless I've ended up committing to the purchase of a <a href="https://www.nexdome.com/">Nexdome</a>. It's a Canadian product but there is a dealer in Australia which saves a bit on shipping costs (not as much as you'd think though). I'm hoping it'll arrive before christmas but honestly I'm not holding my breath...</p>
<p>Now with the dome on the horizon I've also started putting my mind towards the motorization and automation process. Dome automation products are available but like everything else in this field, they are more expensive than I'd like, so I'm thinking I'll try put together my own solution. Achieving motorization with a timing belt and pulley system (driven by a stepper motor) seems like it would be within my grasp. The challenge will be building a dome controller module to interface with the ASCOM platform. As I'll only need a handful of I/Os including usb I think something like an Arduino will do the job. This will require coding of a dome driver and firmware which is likely beyond my skills but we'll see. An appealing alternative would be <a href="http://www.dppobservatory.net/">LesveDomeNet</a> which will allow me to bypass the coding steps but I'd need to locate a specific controller board and from what I can tell so far it seems to be discontinued... No clear path forward here but given more time to research options we'll see where I end up.</p>
<p><img src="https://res-1.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1051.jpg" alt="IMAG1051"/></p>
<p>I haven't been able to test my scope mount since I got it back from the retailer many months ago now. All they've done is regrease the stepper motor on the dec axis so I'm doubtful there will be any improvement to the tracking issue I've been experiencing with it. At this stage I'm seriously thinking about just picking up a higher end mount and relegating this one to observation duty. When I next get a clear night I'll be out there giving it a go and we'll see what happens. That'll probably be my next update so until then...</p>
<!--kg-card-end: markdown-->]]></content:encoded></item><item><title><![CDATA[Building an observatory.. with no telescope to put in it]]></title><description><![CDATA[After a long period with no new content I figure it's about time for an update.
Unfortunately ongoing tracking issues with my mount has put a stop to all
astrophotography activity in recent months. After many weeks of troubleshooting
without resolution I took the scope and mount back to the store. They've
evaluated it and haven't been able to find any obvious issue apart from an
under-lubricated gear. I'm doubtful this is the cause of the issue but I've
retrieved all my equipment and will be tes]]></description><link>https://astronewb.herokuapp.com/building-an-observatory-with-no-telescope-to-put-in-it/</link><guid isPermaLink="false">Ghost__Post__6029194dcf34a2001cc2de1a</guid><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Mon, 03 Jul 2017 05:35:55 GMT</pubDate><content:encoded><![CDATA[<!--kg-card-begin: markdown--><p>After a long period with no new content I figure it's about time for an update. Unfortunately ongoing tracking issues with my mount has put a stop to all astrophotography activity in recent months. After many weeks of troubleshooting without resolution I took the scope and mount back to the store. They've evaluated it and haven't been able to find any obvious issue apart from an under-lubricated gear. I'm doubtful this is the cause of the issue but I've retrieved all my equipment and will be testing it out as soon as I have a clear night for observing. If the issue persists I'll follow this post up with a new entry explaining the problem and how I've tackled it. It's a complex issue that I'm frankly fed up with but spending some time documenting it may help.</p>
<p>In other news I've started building an observatory with my Dad. It's a hexagonal structure with a pier in the centre and we plan to put a dome on top. Construction has been proceeding well and we have the exterior walls up. There's still plenty to be done but not much more until it's functional at least. Pics below.</p>
<p>To start we've mowed down a patch of paddock, fenced it off and setup the profile for our foundations.</p>
<p><img src="https://res-5.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG0942.jpg" alt="IMAG0942"/></p>
<p>We've started digging and putting in posts along the profile. Still a lot more to do.</p>
<p><img src="https://i.imgsafe.org/4bab2a3f2d.jpg" alt=""/></p>
<p>Each post is about a spade length deep with 1 bag of rapidset concrete.</p>
<p><img src="https://i.imgsafe.org/4bab2d81c5.jpg" alt=""/></p>
<p>Posts are done.</p>
<p><img src="https://i.imgsafe.org/4bab7b4de3.jpg" alt=""/></p>
<p>Unfortunately this is about where I start slacking off with the regular progress pictures. We've secured all the bearer beams to the tops of posts. We've been buying materials as we go and that's the latest batch of floor ply and framing timber resting on top.</p>
<p><img src="https://i.imgsafe.org/4babc655eb.jpg" alt=""><img src="https://i.imgsafe.org/4bac3f390c.jpg" alt=""/></img></p>
<p>Floor joists are done and I'm about to start screwing the floor ply down. The pipe in the middle is actually the concrete pier that will hold the base of the telescope mount. We dug a pit for it with a bit of boxing then filled the culvert pipe using buckets. I think I mixed about 20 bags that day, 20kg for each.</p>
<p><img src="https://i.imgsafe.org/4bac139914.jpg" alt=""><img src="https://i.imgsafe.org/4bac69f04a.jpg" alt=""/></img></p>
<p>Fast forward a bit and we have the wall framing up.</p>
<p><img src="https://i.imgsafe.org/4bac3cf405.jpg" alt=""><img src="https://i.imgsafe.org/4bac454aa0.jpg" alt=""/></img></p>
<p>Framing up the roof proved especially tricky. Working with a hexagonal structure and this roof type means you have beams and joists meeting at unconventional angles. These were awkward to measure, cut and fit. Progress slowed down at that point but we persevered and got it done. In these images we've almost finished secured the roof ply and the fascia is up. The bit of ply put up on one wall was a temporary measure to stop the extreme wind we experienced for a few days (yes, we still put the roof on in this wind).</p>
<p><img src="https://i.imgsafe.org/4bacae54a8.jpg" alt=""/></p>
<p>Here we're finishing screwing down the roof. More walls have been put up temporarily so we can more pencil in window and door outlines to aid cutting later.</p>
<p><img src="https://i.imgsafe.org/4bac9b1649.jpg" alt=""><img src="https://i.imgsafe.org/4bac9d3939.jpg" alt=""/></img></p>
<p>We've stapled on the building paper and are ready to put the exterior ply up. We've also sealed the top with a temporary roof to keep rain out.</p>
<p>Current progress isn't too far advanced from that last image. We put ply back up on all the walls and screwed it down. We didn't cut out any of the windows or doors as we were going way for a couple of weeks and wanted to leave it watertight. Since returning the winter weather has really set in so we haven't had much more of a chance to get out there and resume work. This gives me time to work out how I'm going to do the dome at least anyway.</p>
<!--kg-card-end: markdown-->]]></content:encoded></item><item><title><![CDATA[Seeking balance]]></title><description><![CDATA[Part of the setup process when using a German Equatorial mount is getting both
it's right ascension and declination axes in balance. Failure to balance
properly will put additional strain on the mounts motors and gears at certain
points, potentially leading to poor guiding and excess wear and tear.

In practice a slight balance offset can actually be quite useful as it can help
keep the gear train pushing against the teeth of the gear instead of floating
about in the backlash. The mileage of thi]]></description><link>https://astronewb.herokuapp.com/seeking-balance/</link><guid isPermaLink="false">Ghost__Post__6029194dcf34a2001cc2de19</guid><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Wed, 15 Mar 2017 10:55:25 GMT</pubDate><content:encoded><![CDATA[<!--kg-card-begin: markdown--><p>Part of the setup process when using a German Equatorial mount is getting both it's right ascension and declination axes in balance. Failure to balance properly will put additional strain on the mounts motors and gears at certain points, potentially leading to poor guiding and excess wear and tear.</p>
<p>In practice a slight balance offset can actually be quite useful as it can help keep the gear train pushing against the teeth of the gear instead of floating about in the backlash. The mileage of this technique varies depending on the mount and setup, however, the key word here is <em>slight</em>. A large balance offset will almost always result in reduced performance of any setup.</p>
<p>The balancing process itself is fairly simple. Each axis is rotated until parallel with the ground, as this is where maximum gravitational force is exerted at each end. Weight is then shifted until there is no pull on one side or the other when the clutch is disengaged. In the case of the RA axis this is pretty easy as there's a long counterweight shaft to which weights can be added/removed or moved along the shaft to fine tune balance. When it comes to declination it's a matter of shifting the telescope itself backwards and forwards in the mount saddle. This is where I ran into problems with my own setup as the 'foot' attached to the bottom of my telescope, which connects it to the saddle, is quite short and can only be shifted back and forth a small amount.</p>
<p>The solution in this scenario is to replace the foot with something that provides more leeway. My mount package included an 8 inch dovetail bar (dovetail refers to the bars wedge shape and is a common form accepted by most mount saddles) which would suit the purpose nicely. Next I would need a pair of tube rings to fasten the telescope to the bar. I ordered a 100mm pair from Orion as they appeared to be the least outrageously priced option for what is essentially just a piece of metal from a factory mold. As it would turn out 100mm was much too big a size for my scope so all savings were nullified as I had to go back and reorder the correct size of 90mm. For future reference my ED80T is apparently not part of the &quot;Orion 80mm ED Refractor Telescopes&quot; family, as their Tube Ring reference table suggests 100mm is the correct size for them... Anyway, after a few more weeks the rings arrived and I was able to start putting the pieces together. Assembly was a simple matter of screwing the included bolts through holes at each end of the bar into the threadings at the base of each ring. The rings themselves are hinged so the telescope is installed by just seating it in the rings then clamping them down tight enough that the scope doesn't move or rotate. This, unfortunately, is where I encountered a major issue: my scope was too short to accommodate the spacing between the 2 rings. With one ring at the base of the dew shield (fully extended), the other would be stuck beyond the base of the optical tube straddling the focuser. This would be unusable as tube rings can only be secured around the tube assembly itself.</p>
<p><img src="https://res-3.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG0893.jpg" alt="IMAG0893"/></p>
<p>Resolving this problem would require decreasing the spacing of the tube rings on the bar by at least 3 inches. At first the solution seemed obvious. The bar had 2 holes in it's mid section and using either one or both of them would have easily provided the required spacing. Unfortunately the holes in the mid section were threaded and were too narrow to take the provided bolts. I could have acquired some screws to fit but then, of course, they would be too thin to thread into the holes at the base of the rings which were obviously the same size as the bolts. Secondarily to this, having both holes threaded would provide much less of a compression force. To top it all off, the bottom of the dovetail bar needs to sit flush against the mount saddle so having bolt heads protruding from the bottom of the bars mid-section would render the whole thing unusable.</p>
<p><img src="https://res-3.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG0892.jpg" alt="IMAG0892"/></p>
<p>By this point it had become obvious that the only way to get what I needed would be to modify the bar itself. I took to it with a press and drilled two holes into the bar, one on either side of the two pre-existing holes. I really only needed one hole but I figured I may as well do two while I'm at it just to give me more spacing options. I had earlier acquired 2 flat head machine screws to match the bolts that came with the tube rings so countersunk the bottom of the bar to match them. See the final result below.</p>
<p><img src="https://res-4.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG0902.jpg" alt="IMAG0902"/></p>
<p>With the modifications complete I am now able to assemble everything appropriately. The 8&quot; dovetail is only just long enough to achieve balance and I have to shift it almost all the way forward in the saddle but this is fine. The only downside of what I've done here is that I can only use the axis offset adjustment screws at the front end of the bar to correct for cone error. This could be resolved by drilling additional holes under the ring in the mid section so the remaining offset screws could be shifted there but it's likely they'd need to be trimmed down a bit to prevent them protruding into the saddle.</p>
<p><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG0903.jpg" alt="IMAG0903"/></p>
<!--kg-card-end: markdown-->]]></content:encoded></item><item><title><![CDATA[The story so far Part 2: Polar alignment]]></title><description><![CDATA[Polar alignment (PA) is basically the alignment of a telescopes rotational axis
with that of the earth's. The mounts motor system can drive the telescope at a
rate that keeps it in sync with the earth's rotation, but if the mount isn't
pointing directly at the celestial pole then over time the target object will
drift in the scopes field of view. This type of drift is known as field rotation
and the less accurate PA is, the more pronounced it becomes. A bad PA is highly
detrimental to astrophoto]]></description><link>https://astronewb.herokuapp.com/the-story-so-far-part-2-polar-alignment/</link><guid isPermaLink="false">Ghost__Post__6029194dcf34a2001cc2de18</guid><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Sat, 28 Jan 2017 08:17:59 GMT</pubDate><content:encoded><![CDATA[<!--kg-card-begin: markdown--><p>Polar alignment (PA) is basically the alignment of a telescopes rotational axis with that of the earth's. The mounts motor system can drive the telescope at a rate that keeps it in sync with the earth's rotation, but if the mount isn't pointing directly at the celestial pole then over time the target object will drift in the scopes field of view. This type of drift is known as field rotation and the less accurate PA is, the more pronounced it becomes. A bad PA is highly detrimental to astrophotography as it results in star trails curving across the image. It's less important for visual observing, as any target can be re-centered with an occasional adjusted as needed, but it's still necessary to have it somewhere in the ballpark otherwise the GoTo system will be way off target. While my immediate concern was just getting PA close enough for GoTo and visual, I knew an effective solution would ultimately be needed before I could do any astrophotography.</p>
<p>So far my PA procedure had just been to plop my mount down on the concrete, try line it up with the pole by eye, then cross my fingers and hope for the best. I had become quite adept at identifying the pole and it's surrounding star pattern with binoculars but translating that perspective to my manual alignment 'technique' proved to be difficult as none of the nearby stars are very visible to the naked eye. In the northern hemisphere there's a nice, bright star called Polaris that sits almost directly in line with the pole. In the south however, we have no such convenient marker. I would need a new method. Thus began a new research effort.</p>
<p><a title="Anthony Appleyard [Public domain], via Wikimedia Commons" href="https://commons.wikimedia.org/wiki/File%3AOctans_01.gif"><div style="text-align: center;"><img width="512" alt="Octans 01" src="https://upload.wikimedia.org/wikipedia/commons/7/7a/Octans_01.gif"/><div class="caption">South celestial pole</div></div></a></p>
<p>There are several different ways to achieve polar alignment and, as you'd expect, each has their own strengths and weaknesses. It seemed they'd all require a new accessory purchase to be done properly so I really wanted to nail my options down before committing to anything.</p>
<p>The most common and simplest method would be the use of a polar alignment scope. It's a little finder scope that slots into a purpose made housing along the right ascension axis of the mount, that is to say it sits exactly through the line that needs to be pointed at the pole. The scope itself is imprinted with a reticule which needs to be lined up with Polaris and that's pretty much it - job done. It's quite a simple process and the scope itself is also quite cheap; seemingly an ideal solution. As mentioned earlier though, Polaris is only visible in the northern hemisphere. After making enquiries with the local astro gear supplier, it became apparent that no such equivalent exists for the southern hemisphere, or at least not one that's mass manufactured and could be readily ordered. It's still not obvious to me why an SH polar scope is such a difficult proposition. Maybe stars around the southern pole are too dim? Maybe it's just a question of demand more than anything else. Nonetheless I was told not to fret as SH astronomers have a superior and more accurate method up our sleeves - Drift Alignment.</p>
<p>Alignment via the drift method basically involves choosing 2 bright stars and watching for drift in certain directions then adjusting the mounts position until such drift disappears. One of the stars used must be near (within 10 degrees) both the meridian and celestial equator. The mounts azimuth direction should be adjusted until north-south drift of this star is eliminated. The other star must be near both the celestial equator and the eastern or western horizon. Altitude should then be adjusted until east-west drift of this star is eliminated. This is a heavily truncated explanation and there are multiple variations of this method but they all boil down to monitoring and eliminating drift.</p>
<p>The drift method is extremely accurate as you are only limited by the level to which you're able to identify and resolve star drift. No additional equipment is required but having a reticule eyepiece is highly recommended, maybe even essential, as the cardinal directions aren't always obvious when looking through a telescope so having a crosshair to align them against is extremely helpful. The major downside of this method is that it requires constant waiting and adjusting and thus can be quite time consuming. A barlow can help with this to some degree as the higher magnification will help reveal drift direction sooner. Now to me this all sounded great - highly accurate and no large cash expenditure required - but a critical misunderstanding would lead me to discard the drift method as a viable option.</p>
<p>Being that this was early days, I was still yet to wrap my head around a lot of terminology used to describe locations in the sky. Right ascension and declination; arcminutes and arcseconds; celestial horizon and celestial equator, etc - most were concepts that I thought I had a grasp of but in reality I had little idea how they practically applied to what I was doing. When the set of instructions I had referred to the 'celestial equator', for whatever reason, be it a reading comprehension fail or otherwise, I just assumed that meant the terrestrial horizon. The location I observe from is unfortunately surrounded by trees and the northern and southern horizon are obscured to a large degree. That factor, and the aforementioned faulty assumption, led me to conclude that drift alignment could be problematic or inaccurate so I moved on to looking at other PA methods. Later on however, I would come to understand that all I needed was vision of the celestial equator - an imaginary line through the sky that sits in line with the earths equator. The celestial equator is quite easily visible from my viewing spot so the drift method has always been a perfectly viable option. Regardless, despite my mistake, I would end up with something possibly even better.</p>
<p><a title="I, Dennis Nilsson [CC BY 3.0 (http://creativecommons.org/licenses/by/3.0)], via Wikimedia Commons" href="https://commons.wikimedia.org/wiki/File%3AAxialTiltObliquity.png"><div style="text-align: center;"><img width="512" alt="AxialTiltObliquity" src="https://upload.wikimedia.org/wikipedia/commons/6/61/AxialTiltObliquity.png"/></div></a></p>
<p>Continued research would lead me to the discovery of a nifty little product called the Polemaster. It's essentially just a small camera that is attached to the same housing that would otherwise used by a polar alignment scope. The accompanying software uses that view to calculate the center of rotation of the mount, then identifies the exact location of the celestial pole and provides visual cues for the user to make azimuth and altitude adjustments. See below for an excellent video demonstration of the process from Astronz.</p>
<iframe width="560" height="315" src="https://www.youtube.com/embed/R_LgUFZLqIM" frameborder="0" allowfullscreen=""/>
<p>The Polemaster is extremely accurate but also makes the PA procedure very quick. As far as PA methods go it's the best of both worlds, the only downside is the cost. I couldn't find one in NZ retailing for less than $500 but searching online I was able to get one shipped from Hong Kong for under $300NZD (including mount-specific adapter and shipping). The makes the Polemaster the most costly of all the PA methods but ultimately a small price to pay for the convenience and accuracy. Assembly was a breeze and the software is pretty straight forward even though the documentation is a bit ambiguous.</p>
<p>With the Polemaster up and running I was quite easily able to get a good GoTo alignment, resolving my original issue. This made my visual sessions a lot more pleasant as no longer had to manually slew around looking for my targets after every GoTo command. More importantly however, having an accurate PA now meant there was no longer any barrier to getting started with some actual astrophotography.</p>
<!--kg-card-end: markdown-->]]></content:encoded></item><item><title><![CDATA[The story so far Part 1: The beginning]]></title><description><![CDATA[My whole life I've always had a keen interest in astronomy and owning a proper
telescope has always been a desire of mine. Living under the harsh, light
polluted skies of Auckland city would prove to be a strong dissuading factor
whenever the thought would enter to my mind to commit to a purchase - make no
mention of the exorbitant price tags that prevail in the realm of high quality
optics. Moving back to the Northland earlier this year finally presented a prime
opportunity to follow through as]]></description><link>https://astronewb.herokuapp.com/the-beginning/</link><guid isPermaLink="false">Ghost__Post__6029194dcf34a2001cc2de17</guid><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Wed, 18 Jan 2017 08:58:18 GMT</pubDate><content:encoded><![CDATA[<!--kg-card-begin: markdown--><p>My whole life I've always had a keen interest in astronomy and owning a proper telescope has always been a desire of mine. Living under the harsh, light polluted skies of Auckland city would prove to be a strong dissuading factor whenever the thought would enter to my mind to commit to a purchase - make no mention of the exorbitant price tags that prevail in the realm of high quality optics. Moving back to the Northland earlier this year finally presented a prime opportunity to follow through as it has some of the darkest night sky you'll find anywhere. I purchased what is effectively an astrophotography beginners package consisting of an Orion ED80T refractor telescope, an Orion Skyview Pro equatorial mount, a myriad of accessories (see complete listing of equipment <a href="http://www.astronewb.com/equipment/">here</a>) and thusly the journey began.</p>
<p>Being my first telescope I put aside all the photography kit and just focused on visual observation to begin with. The scope and mount were easy enough to setup and use, if a little fidgety. I spent most of my observational time looking at various clusters and planets. Saturn was visible at the time and I was able to resolve its rings quite clearly. Deep sky objects such as galaxies and nebulae were mostly too dim to observe due to the scopes relatively small aperture of 80mm although the brightest DSOs still showed good detail through a 20mm eyepiece.</p>
<p>Through these initial visual-only sessions I would constantly have a problem with GoTo accuracy. I'd tell the scope to slew to a target only to find the object no where in the field of view (using a 20mm eyepiece, my widest available), forcing me to manually slew around nearby space with the hand controller to find it. Part of this problem would be the lack of a reticulated eyepiece making it difficult to center stars accurately during GoTo alignment, but the primary cause would be my first major obstacle: inaccurate polar alignment.</p>
<!--kg-card-end: markdown-->]]></content:encoded></item><item><title><![CDATA[Equipment]]></title><description><![CDATA[
This is a complete list of all equipment I'm currently using.

 * Orion ED80T CF 80mm Refractor OTA
 * Orion Skyview Pro Equatorial Mount w/ GOTO Kit
 * SkyWatcher EQ6-R Pro Mount
 * Canon 600D Camera (unmodified)
 * Canon 600D Camera (modified: LP2 filter removed)
 * Orion Thin Off-Axis Guider (TOAG)
 * Orion Starshoot autoguider
 * Gigabyte Laptop (i7 cpu, 16gb ram, ssd)
 * QHY PoleMaster

> Update 15-02-2021

 * SkyWatcher EQ6-R Pro mount replaces old Skyview Pro
 * Modified 600D replaces un]]></description><link>https://astronewb.herokuapp.com/equipment/</link><guid isPermaLink="false">Ghost__Post__6029194dcf34a2001cc2de16</guid><category><![CDATA[Equipment]]></category><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Fri, 06 Jan 2017 09:35:00 GMT</pubDate><content:encoded><![CDATA[<!--kg-card-begin: markdown--><p><img src="https://res-2.cloudinary.com/hcah7wjy9/image/upload/q_auto/v1/ghost-blog-images/IMAG1401.jpg" alt="IMAG1401"><br>
This is a complete list of all equipment I'm currently using.</br></img></p>
<ul>
<li>Orion ED80T CF 80mm Refractor OTA</li>
<li><s>Orion Skyview Pro Equatorial Mount w/ GOTO Kit</s></li>
<li>SkyWatcher EQ6-R Pro Mount</li>
<li><s>Canon 600D Camera (unmodified)</s></li>
<li>Canon 600D Camera (modified: LP2 filter removed)</li>
<li>Orion Thin Off-Axis Guider (TOAG)</li>
<li>Orion Starshoot autoguider</li>
<li>Gigabyte Laptop (i7 cpu, 16gb ram, ssd)</li>
<li><s>QHY PoleMaster</s></li>
</ul>
<blockquote>
<p><em>Update 15-02-2021</em></p>
<ul>
<li>SkyWatcher EQ6-R Pro mount replaces old Skyview Pro</li>
<li>Modified 600D replaces unmodified 600D</li>
<li>Sold Polemaster. It's mostly redundant now that I'm on a pier and can use &gt;Sharpcap.</li>
</ul>
</blockquote>
<p>The imaging train is assembled as follows:<br>
Focuser-&gt;2&quot; nosepiece-&gt; 18mm spacer-&gt; TOAG/Autoguider-&gt; TOAG canon adapter -&gt; 600D Camera</br></p>
<p>The autoguider is screwed directly onto the TOAG's threading without spacers and without using the c-mount adapter which is attached out of the box.</p>
<p>The OTA is affixed to the mount with 90mm ID tube rings which are fastened to an Orion 8 inch dovetail plate.</p>
<p>Power:<br>
<s>For power I use a cheap 12v jumpstarter just for the mount although I do have a 2.0a 12v ac adapter available which can also power it. I have a spare battery for the camera as well as a recently acquired ac adapter for when mains power is available. The autoguider and polemaster are powered via usb on the laptop. The laptop itself I can currently only run off the battery or ac mains.</s><br>
<em>Update 2/2021</em> - I now image from an observatory equipped with Solar + 100AH battery storage and a 240v inverter. Most equipment is powered by either usb or 12v adapters which connect to the inverter.</br></br></p>
<p>Cabling:<br>
The autoguider, <s>polemaster</s> and camera are all powered by usb cables which come with each respective device. <s>However, I did need to purchase a usb-to-serial cable to establish connectivity between my laptop and the mounts GOTO handset for ascom/eqmod access. The rj11-to-serial cable to complete the connection was included with the mount.</s><br>
<em>Update 2/2021</em> - After upgrading to an EQ6-R, I can now connect it directly to my laptop via USB.</br></br></p>
<!--kg-card-end: markdown-->]]></content:encoded></item><item><title><![CDATA[A brief introduction...]]></title><description><![CDATA[After recently acquiring a telescope and diving into the complex art of
astrophotography, I've very quickly found myself drowning in the technical
details of data acquisition and image processing. I'm approaching the limit of
relevant ideas and issues I can sensibly keep track of in my head so starting a
log of some type seems like a logical step. I've elected to create a public blog
as I figure other new users may find some of what I have to share useful (as I
have with other blogs). Being a co]]></description><link>https://astronewb.herokuapp.com/a-brief-introduction/</link><guid isPermaLink="false">Ghost__Post__6029194dcf34a2001cc2de15</guid><dc:creator><![CDATA[JP]]></dc:creator><pubDate>Fri, 30 Dec 2016 11:29:37 GMT</pubDate><content:encoded><![CDATA[<!--kg-card-begin: markdown--><p>After recently acquiring a telescope and diving into the complex art of astrophotography, I've very quickly found myself drowning in the technical details of data acquisition and image processing. I'm approaching the limit of relevant ideas and issues I can sensibly keep track of in my head so starting a log of some type seems like a logical step. I've elected to create a public blog as I figure other new users may find some of what I have to share useful (as I have with other blogs). Being a complex but also somewhat niche hobby I've found it quite common to encounter smaller issues that it's difficult to find detailed information on, despite the wealth of astro resources out there. Hopefully, if anything, I'll be able to plug some of those gaps and maybe share some pretty images along the way!</p>
<!--kg-card-end: markdown-->]]></content:encoded></item></channel></rss>