ONIKKINEN

Zoom in really close and you'll see that stars are very slightly hollow. Star size measurements also come up with 10''+ fwhm so yes it is well out of focus.

Dont know about tilt and all that, but this sub is well out of focus all over the frame, so hard to advice before that is fixed.

Here is a raw recording of mine from last week, taken with an 8'' newtonian so very much comparable to your C8: Jupiterexample-1600frames.mp4 This was much better than average seeing, and only glimpses of anything other than a few bands are seen in the raw recording. And this was the image afterwards: Point is that its not at all clear when capturing the video whether or not a good image comes out at the end. But generally if you can see anything at all other than the main bands, its going to be a decent shot after stacking. Usually no detail is visible in the recording. If you dont see even glimpses of detail occasionally, then it might be a bad night and not worth the time, but its difficult to tell that without some experience with different conditions.

Maybe useful for IR photometry? Dont need a big chip for that.

I have only ever done untracked planetary/lunar stuff twice, with an AZ5 and a small refractor, but i would say let the planet drift for at least a few seconds untouched before nudging it. Nudging will slightly will shake everything and those frames will probably not go towards the final stack so are "lost" in a sense. If you mess up and lose the planet, but get it back on the chip a few seconds later dont worry about it, you can use PIPP: https://sites.google.com/site/astropipp/ To preprocess and keep only the frames that have the full planet on the chip. I use 640x480 ROI on my tracked setup, and with that Jupiter wouldn't spend more than a few seconds on the chip without tracking, so you might need to use a larger ROI to give yourself some time. @Kon regularly posts stunning images taken with a manual dob over in the planetary imaging section of SGL. They might be able to give you more tips on the manual dob aspect specifically. The focus issue mentioned above is not going to hamper you by the way. The 678 or any other planetary camera for that matter has a very shallow backfocus of 12.5mm so if you can focus an eyepiece you can almost certainly focus the camera. The barlow you will be using will also kick up the focal point a bit, so no worries. If you were planning to do imaging with a long flange distance camera like a DSLR some newtonians fall out of focus. But you dont so no problem.

UV-IR filter for the 678. It has a wider pass antireflection coating on its sensor and without a filter blocking ultraviolet and especially infrared you will get weird colours in the image in the end. This doesn't need to be a cutting edge perfect filter, just get some affordable 1.25'' one. The 678 comes with a filter threaded nosepiece where you can thread the filter to, and you just plop that into the barlow and the barlow into the focuser and you're set. An ADC will help when the planets are low in the sky, but i would say you dont "need" one straight off the bat as Jupiter and Mars later on in the year will be reasonably high in the sky this year. Probably better to start without and get the whole process going without any extra trinkets to worry about since you have a lot of new things to get accustomed to anyway. Re: laptop. File sizes get large really fast with lucky imaging at high framerates. 60s recordings with my 678MC in 8-bit mode and 640x480 resolution are almost 4 gigabytes a piece, so the laptop should have a fair bit of ram and an SSD that can write large files fast. If the disk cannot write fast enough your framerates will tank during capture and you'll lose some data. Pretty much anything with USB-3 capabilities and an SSD will do, but in case you are looking for used ones its probably best to skip the older or cheaper models that lack USB3 and an SSD.

This one (and the previous, but especially this one) is excellent, stuff of dreams - excellent. Background should probably improve a bit if you add more data to it. Maybe it will be excellent^2? Great shot anyway.

Size of the planet in pixels without oversampling is dictated by the aperture, you can expect to get around 180 pixel diameter of Jupiter with yours. You could use a barlow to zoom in and make the image bigger, but it will not have more detail as the limit is not in the focal length, but in the aperture area. The formula of an ideal f/ratio for planetary (f_ratio=pixelsize x 4) is an estimation of the resolution where all the detail of the object can be captured and here aperture is king as it will dictate the maximum size of the object in pixels. You can use that camera in 8-bit mode and a small region of interest to do planetary as well as with dedicated planetary cameras. Thankfully you have 3.75 micron pixels and so no barlow necessary. Using a small ROI is effectively digital zoom and will push your framerates through the roof allowing you to capture the maximum amount of frames over a short period. Be sure to use a USB3 cable! Jupiter (or any other planet) will appear tiny, mushy, and detailless during capture and you will really only see what you got after stacking. Focus is key, focus visually on the planet itself and not with a bahtinov mask. Use 5ms exposure time and a RAW8 video capture with the output file being a .SER file. Adjust exposure by changing gain until you have a well exposed video with no clipped pixels. Stack in autostakkert!3 in the end (as!3 can make the best out of colour data). So in short, you are good to go already, just hook the camera to your visual back with a 1.25" nosepiece and youre good to go.

What camera do you have, and also is your mak F/15? If you have a DSLR you have a lot of empty space that just needs to be cropped out. Alternatively if your camera has a "movie crop" video imaging mode that records 640x480p videos at 50/60fps you can use that (like a 550D). Ideally planetary imaging is done with a planetary camera that connects to a pc via a USB3 cable to facilitate very high framerates. The capture resolution will still be the smallest area possible to just barely cover the planet, because the filesizes get ridiculously large really fast with high fps captures. For planetary imaging the ideal f-ratio is around 4x pixel size in microns (for RGB captures), so actually you are lucky that there are many cameras with 3.75 micron pixels out there that are ideal with your scope straight out the box without any barlows. Not sure i get this bit. Are you trying to do imaging through an eyepiece? Get rid of the eyepiece in between the camera and scope. In that case you would need to get an adapter between your camera and focuser, but that again depends on what camera you were going to shoot with (most dedicated astro cameras come with 1.25'' nosepieces though).

In operation the mini-pc will be free of frost and dew, just due to the fact that it heats up a little bit in use and so keeps the casing above the dew point. Not sure how good of an idea it would be to leave the thing outdoors to attract frost and dew, but probably best to cover it up after use. As for the specs of the thing itself, pretty much all mini-pcs out there are good enough for astro use. With windows 10 and above you do need more ram though, preferably 8gb but most models have at least 4gb so it will probably be fine. I would be shocked if you can find a mini-pc out there with worse specs than your current vista laptop, so the only way is up.

50mm aperture? Thats pretty damn good, i have taken worse ones with 200mm aperture 😃.

The first one had the best stars IMO (and overall look, except colourcalibration wise). All of these look very unnatural to my eyes with mushy and posterized looking stars that are overreduced (looks like star tools took you on a wild ride?). The galaxy itself also looks separated clearly from the background, almost like it was cut out from another image and pasted on this one with unequal levels. the fainter halo shouldnt be all that higher than the background but here it clearly just stops abrubtly and suddenly turns into background. The first image looks good in that way. Apologies if i critiqued a bit too much, but these are just my 2 cents.

The Askar OAG has a 10x10 prism, helical focuser for the guide camera and comes with telescope and camera side thread adapters to M42, M48 and M54. So far i have liked mine and cant find something to complain about. The price is pretty good too if you consider the fact that it has all of the adapters in the box. Also looks like FLO has some stock left of it, so worth considering.

Did you try adjusting the 3 philips head screws under the mount and not just the allen head ones on the side? You probably did, but if you've had the mount on a tripod all this time you might have missed them so worth a shot at least.

Thanks, its always a surprise to see what kind of detail the skies gave this time. Its not at all apparent during capture whether the end result will be a waste of time or a good image. Software made available to the public is doing almost all of the work here, we are lucky to have all the amazing software free to use for amateurs!

Found the best recording of the bunch, this is what the single frame looks like with more attention given to it than the animation: Also, a blown up closeup of Io itself (from a different recording): I can maybe imagine that Io has maybe a couple of pixels of detail on it, but could be just noise too, just found it curious. In theory not impossible with its 1.4'' size and an 8'' scope i suppose. But that halo thing, anyone have a clue what that is? My barlow lens is basically touching the paracorr top lens, so my guess is some kind of reflection between the 2. But could this maybe be some kind of diffraction artifact if its not reflection related? Maybe the airy disk around Io? Dont know how to calculate any of that so just guessing.

Thanks, its a lot of fun to make these. Also a lot of work, so i am glad that some of the nights turn into nice looking shots in the end.

The pointing accuracy of my EQM35 was never all that good, and it did also seem to have its own mind on when to be less good than other times. But you can make things easier with a couple of things. Yes, you should try to do 3- star alignments with the mount and it will imrpove the accuracy a bit, but the problem here might be that you have a limited sky to pick the alignment stars from. 3-star alignment ideally will use 3 stars that are at very different parts of the sky, something that might not be possible for you. A trick that you can do is do the 2-star (or 3, or whichever) alignment as you normally would and then do a final extra 1-star alignment on a star that is close to the target you will image that night. That will increase the accuracy further and if you manage to find an alignment star within the general area of the target you will pretty much always land the go-to afterwards. With the eagle nebula you could use Altair, which is pretty close. This is what i did before i did platesolving. Which bring me to another question. Do you platesolve, if not, why not? Looks like you have guiding so you have all the indgredients needed to platesolve (just a computer basically). With platesolving your setup will auto-center itself to the target and you dont have to do the star alignments at the start of each night anymore.

Thank you! Thanks, yes should have written that i did use a 2.5x barlow on top of the paracorr that also adds 1.15x. The focal length is approx 2350mm with the setup i have now, which is a bit too much for 2 micron pixels but i cant easily shorten it with the kit i have now. The raw recordings are 4 gigabytes, so i took 1600 frames (approx 8 seconds real time) and turned to a lower filesize AVI. Quality has suffered a bit, but honestly not that much and this is a pretty good representation of what it looked at the time: Jupiterexample-1600frames.mp4

Jupiter and Io, with the GRS barely still visible with an 8'' F/4.4 newtonian + paracorr and barlow to around F/12: 15 recordings of various quality spanning around 20 minutes. Seeing varied a lot with pockets of what i assume is hot air passing through the view occasionally, but generally i would say that the seeing was good at the time.

Both with 8'' F/4.4 newtonian + paracorr + ASI678MC. The wide one without a barlow, very simple 1000 frame recording with best 100 stacked: And the closeup of the Mare Humboldtianum, right at the limb. This one is barlowed to ~2350mm focal length: Seeing was OK, at times even pretty good, but the Moon was at 21 degrees of elevation so the captures were not very sharp most of the time. The closeup is best 1% from 25 000 frames, any more and it gets even softer.

Typical 1.5-2.5'' fwhm seeing, typical 0.5-1'' RMS guiding, not quite diffraction limited corrector (for my example anyway). I dont think its a shocking statement to say that 1.24'' will be oversampling almost all of the time. I certainly have never taken a single deep sky subexposure that could even in theory support that kind of resolution.

Is the tube deforming under the tension of the spider supports? Something is not tightly held, or otherwise there would be no movement.

Just another drop in the ocean i would say. People are not complaining about glow from Jupiter ruining their exposures, so why worry about this? People are overreacting to the whole satellite thing in terms of how much it effects (amateur at least) astrophotography. There could be 10 satellites on every subexposure you take and they still get clipped out just fine in the end! Bringing easier to access internet to the world is an overwhelmingly net positive thing in the grand scheme of things anyway, so i say go for it and build the giant eysore.

Processing wise, cant tell, since i am not behind the scenes pulling the strings on the levels. Just something about this one that "pops" out from the other ones, cant be more specific than that! But what i can tell is that you have managed good star shapes on a challenging target (its a tiny galaxy and the stars are still good = top tier stuff!), and good overall dust lane detail on this one. Maybe one of the earlier decon ones were better in terms of detail, but as you worried i felt they were maybe too hard on the mottling effect. This one just "feels" the best 👍.