ONIKKINEN

I would set the Output Format to a video mode (SER maybe?) where all the frames are in a single file. If you plan on actually completing your 10 000 frame sequence with your current settings you will have 10 000 individual TIFF files.

Tolerance settings changed for some reason? I have mine on 0.5 arcmin and it is always centered, but sometimes takes several tries to get there. If it takes more than 10 tries however NINA stops the platesolve-reslew sequence and just hopes its on target and shoots. If you have the retries set to a low value like 5 and you get gusts of wind or something else you could run into the retry limit. ASTAP is quite picky on starshapes, if its windy my platesolving fails with the EQM35.

Yes, from your posted TIFF! It did take a lot of stretching and saturation boosting (selectively on red in the end) to bring out anything. Without trying to fix the vignetting with flats or in my case background extraction tools you would not see anything really, since the image breaks down soon in the edges. Its difficult to process because of the lack of flats, IMO and you would easily get a nice result if the image just had flats. Cant stretch the image very far when there is severe vignetting everywhere except the very center of the image. Quick fix you can try now, even later after the images have been taken would be to try and get every setting as they were during imaging and take flats now. Aperture and focus must be the same. Focus will be difficult but maybe focus to infinity on a terrestial target and then take the flats? They probably wont be a perfect match to the conditions you shot the lights in but much better than nothing. You can take flats by just pointing the camera to a computer monitor/TV/tablet or whatever device showing a white screen with minimum brightness. Use AV mode with the same ISO as the lights and there you go, flats taken (take maybe 30 or more, move the camera a bit between a few shots to even out dead pixels/lighting differences in your monitor). You would be surprised how easy the image is to process once you stack it with flats and bias! And by the way, flat frames are necessary with the dedicated astro cam as well, cant really skip this calibration step if you want processable images.

I would agree with @Rallemikken with the focus and tracking. Your starshapes have an elongation along the DEC axis, indicating polar alignment issues. Could also be mount shakiness in your DEC axis if you touched the camera every time you took a picture. If the latter is true, figure out a way to shoot without physically touching the camera. What mount was used and was it polar aligned? a 6'' refractor will be a heavy load for most mounts, so i am willing to bet this is a major part of the issues.

This image is a prime example of why flats are NOT optional if you want to be able to process an image to its full extent, you really do need to take them! There is a lot of signal in the image that just needs to be stretched out. But without flats this is unnecessarily difficult and requires some bruteforce background removal, which by itself has a tendency to wipe out faint detail (at least with my processing skills). I am sure someone could do better than this but here is my try with Siril and Photoshop: i think youll agree its far from wasted and there is a lot to look at here. I tried to shield the 2 biggest/most obvious patches of nebulosity when running GradientXterminator but the process could have very well wiped other parts that would be visible with a calibrated stack. The cooling part is only a part of the deal, and not the "main" reason dedicated astro cams are better than modified DSLRs. The cooler acts as a set point temperature device and allows calibration to be done properly regardless of temperature outside, which is something that is impossible with DSLRs. I dont know about the 5D MKIV but many Canon DSLRs do some weird stuff in the background to dark frames, which makes calibration difficult. My 550D always has a median ADU of 2048 in dark frames, regardless of exposure length and temperature, which means that dark frames do not work as intended. Dedicated astro cameras dont have these "hidden tricks" in them and you really do get the pixel value in raw format straight out the sensor. If you buy one of the newer backlit Sony sensor cameras you will also find that QE is a lot higher than really any DSLRs on the market. Higher QE just means that you get more out of the same time spent imaging with no drawbacks, it is just better. For example the 5D MK IV apparently has a QE of 56%, whereas the new backlit Sony sensor cameras have somewhere around 80% (for color sensors, for mono it is closer to 90%). The full frame format of your camera could actually be called a drawback for many situations. If you want to use a telescope one day you will find that scopes that can produce a good image all the way to the edges of a full frame sensor are quite a lot more expensive than scopes that work to say APS-C size sensors. The small IMX533 sensor is an issue for some targets, true but you could work around this by just shooting smaller targets. There is a lot more to it than just cooling, and dedicated astronomy cameras are just flat out better than similarly priced DSLRs. But they are very expensive (like everything related to cameras, so not a surprise really).

No sudden windows updates is one of the biggest bonuses of having a disconnected scopeside PC IMO. I see no reason why windows would need to be updated when all the capture software works just fine. I dread the idea of having to update my mini-pc which has never been connected to the internet...

Thought so, grubscrews are off but still it wont budge with my McGyver'd tools made with what i have (some bolts and leverage, bolts broke off). Probably need to head to the hardware store to buy the proper pliers for this. Its unnecessarily tight for me, but its only an issue with the latitude set to higher than 45, so where gravity no longer helps with the movement. The synta factory at Taiwan latitudes does not have this issue since its at an easier angle where gravity helps with RA movement. At 60 degrees north not so much.

Actually my brand new mount has this issue, the locknut is too tight. Difficult to balance with stiction in RA with the clutch off. What is the proper tool to open this if i may ask?

I prefer the unbinned version too. But looks like processing has taken different turns otherwise, so difficult to compare when other aspects of processing are different. But doesn't matter, its a fine picture anyway!

Very good price regardless. As some have stated you may have issues with not having a tilt plate or the sensor window heater not being strong enough and having to use a UV/IR filter. These are not that expensive to fix anyway and it will still be well priced compared to the 2600MC.

No VAT paid during checkout and hope that customs buy the fake price declared on the package? I was asked what price i want declared on the package too, but i would not risk it. Customs agents are not idiots and i think its safe to say they can recognize the package as something more valuable if they lay their hands on it and will open it if there is a question. Once open they find out what actual product it is and demand a receipt stating the exact price. Not worth the trouble IMO.

I dont know if this gear is supposed to be able to move or not so wont comment on that, but definitely dont file anything off it. You can heat fit it back in pretty easily. Its not rare for gears and fittings made of different materials to be stuck, and especially once they have been used. Heat the brass gear and cool down the inner axle and it will go in with less use of force. Maybe throw the axle in the fridge for a while and the brass gear into an oven at low heat. Dont heat it so hot that you cant touch it with gloves, so just a while in the oven. This way you can fit it back in pretty easily, but i dont know if its supposed to be able to move on its own so maybe dont do that until you know.

Here is an example i found from my catalogue of subs: First one is straight after setting up on a night when i did not have time to cool down the scope properly. Second is 2 hours later.

Looks like the kind of artifacts i get when my newtonian is not properly cooled down and tube currents are still present. Did you image straight away from setting up outdoors or wait a while? Sometimes it can take about an hour for my 200mm to be fully ambient and these artifacts go away. Check the your early subs and compare them to your last ones, if the early ones look like this but the last ones are clean this was caused by tube currents.

While guiding is not strictly essential to get going it makes little sense to image unguided for long due to the limitations, so do try to leave budget for guiding gear as well. I am not that familiar with the AZ-EQ5 but i would imagine it doesn't do unguided all that well since really nothing does at this kind of pricepoint. You might get away with using short subs unguided but ideally you would be guiding as soon as possible. Guiding gear can be as cheap as the cost of the guide camera and an adapter for your existing finderscope (if you have one), or a guidecam + guidescope + guide computer = probably looking at least a 500 pound investment at this point. Less if you have a laptop you could use as the scopeside computer. Again, not necessary to take images but you will probably find that 30s exposures are the best you can do and even then many of them are unusable. Also, leave some budget for the trinkets one doesn't normally account for: adapters for your corrector and camera, power supply gear, cables of all kinds, trips to the hardware store for tools and some random bits you may need, processing software (not always necessary, free ones are pretty good) etc. It all accounts for a lot of money in the end. I poured all of my initial budget when getting into astrophotography into a mount and a telescope, and then once i figured out i would need many extra trinkets and bits to get the thing going properly i had no money to get them, so the gear sort of trickled in paycheck to paycheck. Also made many bad purchases "to save money" because of this and in the end did not in fact save money 🤣.

I have never worried about cooldown quickly, as there is no risk of dew then. Dewing happens the other way around, when cold things are brought back inside. I have a carrying case where i put all my electronics after a session outside and only open this after about an hour from being back inside. This gives them ample time to warm back up slowly and dew/frost does not get a chance to form on them. Maybe a bit paranoid and overkill, but costs me nothing, unlike the electronics which cost a lot.

Like this? 😁 Did this when my battery pack died in 20 minutes. Had the cable through a gap in the passenger side door drawing power from my center console 12V plug. Engine running to ensure the battery doesnt die on me. Pictures werent good but everything worked just fine.

My EQM-35 worked as well as it ever worked down to -26c (= not that well). Balancing will be even more difficult than normally since the lubricant gets really stiff, but other than that i doubt you will break anything. Just dont try to bend the cables after the night is done, they get very stiff and you could break them. The DSLR will work very slowly and drain batteries very quickly, expect to get maybe 30min of exposure per fully charged battery. And also, your power supply for the mount must be high quality in these temperatures. Normal "dumb" powersupplies like batteries that are unregulated will drop below 12V much faster than you'd think so a good power solution is necessary if you want to image for any length of time.

Judging from the diagram it seems that this camera also has very low dark current. Below -5 its arbitrarily low and probably doesn't cause any issues. At your temperature of -10 there is 0,0768 electrons of noise in a 120s dark frame = so pretty much irrelevant. Actually judging from this you could run the camera much warmer and probably still not see a difference.

Its the thing dark frames are for. When you expose for a dark frame in complete darkness you still get signal in the image from thermal noise. When dark frames for flats are not available (darkframe with same exposure length as flat frame) a bias/offset frame is subtracted from the flat. But in your case the bias frame is 1/50s and the flat frame is 1/7s, so its possible there is unaccounted for signal in the flats = calibration doesn't work as intended. Reason i said its a gut feeling is i dont have nearly as much dark current in my camera, so bias and darkflat are similar enough that i dont care about the difference.

Had a quick look as well. Flats dont seem to be working all that well and the end result has inverse vignetting for me. I dont know anything about the ASI1071MC so probably not that helpful for you but shouldn't bias frames be as short as they can be? Your bias frames are 1/50th second and the flats are 1/7th second exposure. Probably necessary to take dark-flats then to calibrate the flats properly. Looks like there is some dark current in the dark frames aswell so it could result in bad flats calibration. I dont really have dark current in my camera so cant comment on that on more than a gut feeling stance. Also the flats have a very different vignetting look to them per color channel.

Browsing through my available catalogue of subs i find that there is somewhere around 1-1.5 magnitudes of difference in sky brightness (18.5-20) for nights with no moon vs a night with a full Moon. All of my examples were such that the Moon was on the opposite side of the sky, so it could be much worse but far from wasted. There are more than 4 magnitudes of difference in people imaging from dark skies vs very light polluted skies and both can take good looking images, so no real reason to shy away from imaging with the Moon in the way. Of course an hour from a no Moon night will be more valuable in terms of signal to noise ratio than an hour with a full Moon, but it wont be "wasted" like i fear some people might think. The only way a full Moon can make me lose imaging time from broadband DSO imaging is if i decide to shoot the Moon instead.

Ah, i have seen the opposite of that: a bright spot suddenly. Probably high cloud if not dew related then. Is it this one you installed: https://www.firstlightoptics.com/zwo-accessories/zwo-anti-dew-heater-strip-for-asi-cooled-cameras.html ? Probably should get one just in case, would hate to run into this issue if i head to a darksite off the beaten path one day. Im curious on the situation this happened in, could you tell what the ambient temperature and sensor temperature was at the time? This time of year my camera cooler is basically idle at 5-10% power usage due to low ambient temperatures so dew is less likely to form, but when spring comes this will definitely change. Last spring i was not running a cooled camera yet but dew in every nook and cranny was an issue every time i went out.

Is this easy to spot when it happens, or is it a subtle change in sharpness? I have issues with the latter but always assumed it was just guiding or something else. I too image in the "danger zone" of dew most of the time, so 90%+ humidity.

I use this one: https://ecoflow.com/products/ecoflow-river-portable-power-station although not sure if its available in the UK. Jackery branded similar specced powerstations do appear to be available in amazon. But this one will run an observing (non imaging, so no power hungry gadgets outside the mount) setup for longer than you could ever use it in a single sitting. The DC- side is regulated to 13.6V, although this does change depending on the payload. But never goes below 12V, or even that close to it. For imaging power needs it still easily lasts longer than my patience when outside, so has never run out. I had a bad experience with the smaller Celestron in your links, wouldn't recommend that one. Could not supply enough power to do GO-TOs consistently and auto shut itself down very often. Was never able to use it for anything serious, and that was with a small EQM35.