discardedastro

I've left my gear outside for over a year now. Telegizmos 365 cover does for the rain. It's insured against theft by an insurer recommended by I think the BAA, but the insurers wouldn't cover it for weather damage outside of an observatory! Cost me about £9 a month, which given the value is worth it in my eyes. Still feel twitchy every time there's wind or heavy rains - but so far it's been absolutely fine through some major storms. Having the kit out full time is a godsend for setup and tweaking - it's all cabled up permanently except for power, so I have to run a 30m extension lead out and plug in a 12V supply. I'm hoping to get even that permanently sealed up outside soon.

Six hours of L, an hour of Ha, and about 2 hours each of RGB. Baader filters (7nm Ha) and ASI183MM-PRO on a 200PDS, EQ6-R tracking. This was made up with a few nights of capture in March and a little bit of data I captured back in mid-2019 - the former providing much more quality data than the latter. Processing was with PixInsight exclusively; calibrated with darks+flats, integrated with a mix of Linear Fit and Generalised ESD plus large structure pixel rejection, weights from SubframeSelector. DBE'd all masters, deconvolved all masters with a DynamicPSF-generated PSF, combined RGB, BackgroundNeutralisation, PhotometricColourCalibration, MLT denoised, Histogrammed, LRGBCombination, fair bit of RangeMask jiggery-pokery to denoise and desaturate the background without messing up the fainter nebulosity, very light pass of HDRMT, tiny bit of masked LocalHistogramNormalisation, and final bit of MLT sharpening. Denoised Ha and DBE'd separately and combined with NBRGBCombination script. Overall quite happy with this - going to try going deeper on some of this, but it's been nice to get some lower-noise stacks to work on than my usual shorter runs. LRGB only:

Just more of them, I think, though hard to say without seeing an individual sub.

Gave this a go in PI - there's not much in terms of SNR between the fainter areas of nebulosity so a bit more exposure time will help that, but it's otherwise fairly clean data. Vignetting might be tilt, in which case you can get a tilt adapter for T2 trains - Teleskop Express do one - but it isn't significant and if you do flat fielding correctly should calibrate out nicely. Same goes for the dust motes, though cleaning is always preferable!

Yeah, I'm definitely going to recapture a bunch of darks soon since I'm only using 7x300s which isn't ideal, but for this image I used BatchPreprocessing with some pre-made master darks for the first time and I'm fairly sure this forced the optimisation setting on. Was only intended to be a quick stack to see how it turned out, but certainly if I reprocess will do so from scratch so I don't hit that.

Been doing M101 a lot lately but thought I'd give M51 another go - just grabbed one evening of data, didn't combine with one of my previous datasets but might do so later. Acquisition was on the 200PDS/EQ6-R w. an ASI183MM-Pro and Baader LRGB. 22x300s L, between 5 and 10x300s RGB. Processed in PI - calibrated, stacked, DBE, deconvolved, combined, denoised, local histogram equalisation to bring out some of the detail in the arms, and a bit of saturation boosting. Final DBE and then TGVDenoise to finish.

You can connect everything up beforehand no issue. I'd suggest using PHD2 for guiding. You can set the gain manually in the INDI control panel in KStars, which will probably help - it might have defaulted to the max gain. Be sure to save the configuration on the INDI driver when it works.

Just remember to set your "active hours" in Windows Update settings to cover your observing hours so you don't get Windows Update reboots mid-session!

If you're wearing eyeglasses then have you had them inspected? I recently trekked into London to visit an independent optician just to check as I wasn't 100% confident in the high street opticians but my prescription hadn't changed a bit. The coating on my glasses however was scratched from cleaning, causing some issues - the fix is simply to get the glasses reglazed or replaced with the same prescription, which I'll be doing soon.

Nope, around the lens cell - you don't want to heat the air directly because you'll get turbulence and currents.

I believe this is the case. The other option - which I'm about to go and do - is to fit a digital setting circle like a Nexus DSC to the telescope. That doesn't get you automatic motion or tracking, but does make shoving the scope around easy.

Hoping to be there, travel and COVID-19 permitting.

Yeah, fair enough. I do hope INDI continues to be as widely adopted as it appears to be getting so far - cross-platform drivers and interfaces with a neutral interchange format can only be a good thing, and a huge improvement on ASCOM. I'm envious of the ASA mount - my EQ6-R Pro isn't even in the same league.

I'd heartily recommend the use of Linux for any observatory control stuff - much more reliable and less prone to things like random reboots to do Windows Update in the dead of night when you're not using your PC it isn't so scary, and KStars/Ekos/INDI is an excellent stack to use. Raspberry Pi 4s are cheap, cheerful, and incredibly capable for the cost. Otherwise any NUC will work just as well on Linux as on Windows.

Not entirely happy with how this came out but thought I'd share anyway. Focus wasn't great, seeing wasn't great, etc, and only captured under a full moon. Processed with PixInsight using a fairly normal workflow for mono, deconvolved Ha very lightly, combined with NRGBCombination. 5x300s LRGB, 14x900s Ha. ASI183MM-PRO on a 200PDS, EQ6-R Pro, PHD2/INDI/KStars.

SSD vs HDD is the single biggest win you can have for performance in PI. SSD performance relevant to PI is the sequential read-write perf, which many cheaper SSDs won't be terribly good at. NVMe disks like the Samsung 970 EVO series will be absolutely best - and can go into pretty much any machine with a PCIe x4 slot spare with a £10 adapter. That's definitely the single best upgrade I did for my old rig, and of course the disk is modern so can be reused if you do go for an upgrade. AMD vs Intel is also particularly relevant if you're building a new rig - Intel have much less PCIe I/O on consumer (and even server) parts than AMD, and so I/O can be much faster on AMD platforms. Plus, they're a bunch cheaper - and if you look at the benchmarks site you'll note that AMD systems are currently trouncing Intel systems that cost two to four times more. PI can parallelise very well, which also makes it a good fit for the higher-core-count AMD parts now out like the 3900/3950X series. Well worth looking at that world. Mid-level parts like the 3700 and last-gen 2xxx are also worth a look for a budget build. Just make sure you have RAM to match - 32G is a minimum in my opinion. https://pixinsight.com/benchmark/benchmark-report.php?sn=AHPMET8XQINSKAD45P47813ZH07815BN is me Took me about 14 seconds to open your photo, entirely CPU-bound - I would guess that working with that debayer pattern is quite intensive, since similar frames but from a Nikon Z6 only take a few seconds. It used to take me (on an i7-2600K) best part of half a day to put an image together using mono frames; I can now do that in under an hour. My laptop, an i7-8650U, is much clunkier but that's partly down to thermal throttling.

Ah, tricky. Have you looked at OAGs combined into filter wheels, or a Paracorr? The Paracorr has a mild barlow effect and so pushes the focal plane back considerably, which should then give you the required back focus.

GIMP is fantastic, but if you're going to spend any money on image processing software for photos, PixInsight is the way to go imho - I spent money on StarTools and others before PI and haven't touched them since. However, I'd also add to the already-high cost of PI the excellent Inside PixInsight book - it is the missing manual.

With a dob that big I'd be looking to move to an OAG, since at least some of your error is going to come from differential flexure and mirror support/positioning changes. If you do go to an OAG then sensitivity is a key aspect though with a 10" dob you'll be doing alright for light to start with!

Flats are definitely the correct answer for dust. This calculator can help you find which surface the dust is on, too: http://www.wilmslowastro.com/software/formulae.htm#Dust

Definitely make sure you're generating logs and maybe enable star loss image storage. You can disable star mass tracking but it is generally desirable especially if you're running unattended.

Thanks for all the comments and suggestions - loading everything into Stellarium definitely helped get my eye in! I'm thinking that to get "one eyepiece to rule them all" then spending a bit more and going for the 21mm Ethos might be the right approach to start with - it frames a lot of targets well and using the Powermate would give me a lot of flexibility. It's a bunch more than the Naglers of course, but I can just about cost it in (especially if I leave the Powermate for now and just get the Paracorr). My only worry with the Ethos is just how much of the field ends up being in the periphery and therefore how much of a practical upgrade it would be from the Naglers. Looking around the Explore Scientific 82 degree series also look interesting at considerably less cost but the lack of the Dioptrx corrector is a downside.

With the exception of using some chunky 10mm glass chunks instead of nuts I've done what you've done - how did you clean your tool between grits?

OK, so starting 180 grit with a new tool that I can clean properly is going to be the right thing. My thinking is: Cast a new plaster tool back on the coarse-ground mirror using the same dental plaster I've been using - the plaster's held up well all things considered, I've been cleaning it through dunking it in water without issue Epoxy seal the back and sides as before (possibly with some harder-curing epoxy/resin that won't let things embed quite as easily as this stuff has) Once dried, thinly coat the front with epoxy and press the glass tiles in firmly - I think this should preserve the curve fairly well without epoxying the mirror to the tool (I'm not yet ready to get my pitch on) Rather than try and cut down my really thick glass I'm planning to use these: https://www.amazon.co.uk/MosaixPro-302-Piece-Glass-Tiles-White/dp/B004QTT4RQ/ref=sr_1_56 - they're 10x10mm, 4mm thick, so should last, are small enough they should take the curve on well but won't be a nightmare to clean around. Then once it's all set I'll melt wax over the lot and sides and crack on. My more accurate indicator arrived today, so I'll see how the mirror looks with that in the spherometer - might do a last bit of 80 grit tool-on-top if it's needed at the edges.

Not so much a learning curve as a cliff, but it made a world of difference to me vs StarTools/DSS/Photoshop to have specifically astro-focused tools across the entire processing workflow. I'd budget for a copy of "Inside PixInsight" as a requirement, though - it's the missing manual!