szymon

I'd get a used set of Canon IS Binoculars. Older models go for that kind of price and frankly they're the best easily portable views I've ever seen in dark skies.

Oh interesting, I'm surprised to hear that. Avalon claim that the EQ6 is the root of all evil and that's why they moved away from it to StarGo! Do ask if he'd be interested in selling (although I've just had to pay a yucky tax bill so money right now just isn't available, but I'd be interested in knowing if it'd be an option..).

Crazy. Is yours the older EQ6 motherboard like mine or the newer StarGo board? (And if the latter does that mean you have a spare ? 😉).

Yes, that was me 🙂. Avalon were excellent, I only had to pay for shipping for the belts. Attached is the reassembly tutorial they sent me, should give you all you need. -simon linear-reassembling-tutorial.pdf

Update: I've been doing some digging and I now understand things are meant to work with this scope. Here is what you will get with the scope without any reducer (it's naturally flat, due to the built-in flattener😞 This matches up with my experience -- the stars in the corner at APS-C are nice and round, and it works pretty well for galaxies at f/8. Yaaay. Now, with the reducer I have, 0.7x which gives me f/5.6, the stars in the far corner look pretty odd when you go in close up: and indeed that's been my experience. However, as evidenced by my soul nebula above, they do round off nicely in stacking (and it's only in the extreme corners). Finally, there is another reducer available, 0.77x which gives me f/6.16, which should in theory give better results in the corners for APS-C: In fact, this reducer looks like the stars wouldn't be "too bad" in full frame even (based on how my APS-C stars round off with the other reducer). For now, I think I can live with the 0.7x and deal with the stars in the extreme corners; as mentioned they do seem to 'round off' in processing. If the 0.77x turns up for sale inexpensively somewhere in future I might get one, but it's not vital imho. -simon

So, with my ASI1600 I did manage to get perfect round stars in the corners using the #37228 0.7x reducer (using a Gerd Neumann CTU to adjust for tilt). However I have now moved up to an APS-C IMX571 camera (the Altair 26M) and it is indeed impossible to get perfectly round corner stars with it, no matter what distance I have from sensor to reducer. Without the reducer at f/8 I get a perfectly flat field, so it’s just the reducer which is not capable of properly handling APS-C — which is disappointing, because it’s sold specifically as an APS-C capable imaging scope! Do you have any sample images with an IMX571 camera and the new HD reducer by any chance? It might be worth me investing in it — it’s currently galaxy season and the 825mm f/8 actually works surprisingly well from Light Polluted London (bortle 8, 18.25 SQM on a good day). However longer term I think I can live with f/6.16 and 635mm if I know for sure that I can get good corner stars 🙂 It’s actually not *that* bad with the 0.7x — I may just live with it as the stars do round off a little in stacking (a couple of my sample images attached — soul with the reducer, bode’s/cigar without) but it’s going to bug me...

For planetary stacking, I run VMware fusion and either registax or autostakkert. Siril native on the Mac can do planetary stacking by all accounts, I've seen some nice results but never tried it. For DSO stacking I use PixInsight, but I don't think it's designed for planetary.

This has always been one of my favourite nebulae -- I have a thing for dragons (the fighting dragons are my favourite in the southern skies). Since I image from Bortle 8 LPLondon, I wasn't sure whether I'd be able to do justice to this very faint nebula; there is no signal whatsoever on my individual subs! Nonetheless I am not displeased with the results. This image was taken with a new setup for me, and it does have some obvious defects. First off, the corner stars are a mess -- I have tilt and spacing issues, and I am waiting on some adapters to arrive so that I can fix them, so this is a "best efforts" spacing only 🙂. In addition, when taking this image I didn't yet have my DeepSkyDad AF3 set up on the Vixen, so I was focusing by hand with a Bhatinov mask. The focus seemed to hold pretty well (I had heard horror stories of Vixen focusers but the one on my quad seems to be very good indeed), but I'm sure it could have been tighter (I usually set up an AF run if HFR increases by 10%). I do feel that my processing lets me down somewhat. The final edit I chose brings the Ha and Sii into the Red channel at around the correct frequencies and uses the stars from the RGB frames. My original idea was to just go with a duo-band Ha/Sii presentation, but it didn't really have the depth that I wanted, so I grabbed some RGB in order to get the star colours. I will probably go back to the data at some future point and process it again. Total of 32 hours exposure: • 240 x 300s Ha • 90 x 300s Sii • 18 x 300s R,G,B Hardware: • ZWO ASI1600MM-Cool • Vixen AX103S Quad • Vixen 0.7x Reducer • ZWO EFW3 Filter Wheel • Antlia 36mm 3.5nm SHO Filters • Baader 36mm LRGB Filters • SkyWatcher HEQ5 Mount • SkyWatcher Evoguide 50ED • Altair 290C as Guide Camera Software: • N.I.N.A. -- Capturing • PHD2 -- Guiding • ASTAP -- Plate Solving • EzSuite — LiveStacking and Processing • PixInsight — Final Processing Tweaks

Their support page is misleading; they’ve been asked to remove the support claim until they actually implement it 🙂.

Absolutely lovely! Shame about the Oiii — I suppose those posting HOO are just showing Oiii stars and no nebula. Good to know!

3.2 Gigapixel camera made out of 189 individual...CCDs. Should have gone with new generation BSI Exmoor sensors from Sony. Let the flame wars begin 🙂

This sums up almost exactly my thoughts on the matter. Perfectly encapsulated. Yes it's not an 'astrophoto' in the way that we usually understand it, but it really makes it stand out. I look to the skies to spur my imagination; I am not a scientist, I am an imager; I see the future and the past, civilisation and void, the possibilities of life and the unknown. That is why I keep my eyes (and cameras) to the sky, and I very much appreciate the winning image.

Whoops, yes you're right, google failure. The point however is that the diagonal is such that it should be reasonable, with flats, in the imaging circle of the scope. Pythagoras says slightly under 20mm diagonal with those sensor measurements...

I am thinking future plans for my guide scope and ASI1600MM, along with a TS Optics filter drawer. The filter drawer is 10mm, and it fits direct to the camera's 6.5mm male M42. I'm thinking it will work as a very portable light-weight setup, and I don't think it will vignette more than can be handled by flats (28mm imaging circle, 13x10mm sensor). I will give it a try at some point and if the flats correct the vignetting enough then I'll consider the flattener for megaportable...

Wow, that's nothing at all. Considering the quality of your gear (although I know very little about CCDs but I assume those are sensitive) perhaps there just really isn't anything, and the HOO images that are out there are just the Ha against background and stars.

What I saw in a couple of hours integration was ridiculously faint, to the extent that I wasn't sure that there was anything there at all, but I have seen others post HOO images so I'm basing my assumption on that. If not then I'll be trying various Sii and Ha combinations (HSS vs SHS vs SSH should give the three main dragon types from DnD, for the other geeks out there ;-)).

I dug out a screenshot of the Ha when I last tried this. Bear in mind that this was with a fan cooled (not set point, so effectively uncooled) 183M (so tiny little pixels) via an 80mm Celestron 80ED (f/6 with reducer) from Bortle 8 LPLondon, going through an inexpensive 7nm Ha filter. I think this was two hours, so it's ridiculously faint. Definitely going to be my first 'proper' target for the new scope 🙂

Excellent! So an SHO or other rendition should be possible. I think the moment I finish getting my new vixen tweaked (it’s close!) this will be my first target.

There is definitely some faint Oiii there. My plan was for bicolour HOO to start, and then see if there is any sii. That said it’s very faint indeed - I picked up a little and then decided to wait until I can afford better filters. I now have 3.5nm filters and I intend to get back to it. Here is a bicolour ha/oii by someone else https://www.astrobin.com/310299/?nc=user

Very nice indeed -- one of my favourites (I love dragons in the sky -- this and the Southern Hemisphere fighting dragons are the two I like best!). I took some Ha a while back and intend to go back to it at some point (I am in Bortle 8 so RGB is difficulter). Your data and framing are wonderful.

Set up a mini pc with all your astro software, then connect to it remotely. This article has a lot of relevant ideas. https://darkskies.space/mobile-remote-imaging/

Get focus close manually first (remove the belt to do this). Once it's close, put the belt on and hit AF in whatever software you're using.

I forgot to say, since you're using GIMP here is a useful tutorial about processing astro images in GIMP. Ruzeen explains things nicely, well worth watching.

I am certain that you have a lot more in that data than the picture you produced shows. You need to learn to tease it out. The best advice here is for you to spend some time learning to process your data. This is where a lot of the skill of astrophotography actually lies. Anyone can follow instructions to polar align a mount, point a scope at the sky and take images. But in this day and age of digital imaging, it's what you do with the data you get that matters! I'm attaching a photo to encourage you. The attached image is not great in any way. There is very little actual exposure time, less than half of what you have. Worse, this was taken from my back garden, in Light Polluted London -- Bortle 8 on a good day, but there was also a full moon (this was on Saturday). There were clouds all around, I only had the scope out to work on getting my spacing and tilt correct and then when I gave up on that (you can still see how off it is from the photo) I decided to use M31 as a test image. I pointed the scope and managed to get 31 minutes of exposure, 7 x 60s L and 4 * 120s each of R, G, B (I am using a ZWO ASI1600-MM Pro with Baader LRGB filters), through thin high clouds before the thicker clouds really came in and made it impossible. This is way way less data than your image, and I guarantee that the quality of the data is lower, but processing it correctly managed to pull out the following: Once stacked, my processing steps here in PixInsight were (from memory): On L: DBE, deconvolution, tgvdenoise, mmt for NR, arcsin stretch On each of R, G, B: Multiple levels of DBE (more interested in getting rid of the gradients than preserving detail), arcsin stretch LRGBCombination, histogram stretch, Photometric Colour Calibration, curves for saturation hue and contrast, local histogram equalisation, mmt, mlt That's what worked on my data. It will be different for your OSC data. You might use different tools, you might stack in a different program, etc -- but whatever you use, I encourage you to keep going, because the data is there, you just need to pull it out! If there is this much in half an hour in bortle 8, I am absolutely certain that you can get more from over an hour of the same target in bortle 3/4 🙂 -simon

If you're getting a good price I would go for it. The CEM25P is as you say discontinued, but I am sure that it will be supported for a good while yet. It has a good reputation and it is very lightweight compared to other options. Also, if you find you want a different mount in future it will be trivial to sell on. If you're not going to get it please DM me a link so that I can do so 😉