Vroobel

Both USB C fully support USB 3 Gen 2, so excluding the powering if one is for that purpose, you have 2 x USB A 3.2 (Gen 1 and Gen 2), 1 x USB 2.0 and 1x USB C Gen 2

The Mele 4C 16GB RAM and 512 GB SSD seems very good, Cuiv the Lazy Geek reviewed it. Amazon has a bargain now: https://www.amazon.co.uk/MeLE-J4125-Computer-Portable-Ethernet/dp/B09TKM8VGT/?_encoding=UTF8&pd_rd_w=Jk602&content-id=amzn1.sym.f4bf6248-c25e-4846-ab32-07f8b3e1cc4d%3Aamzn1.symc.afd86303-4a72-4e34-8f6b-19828329e602&pf_rd_p=f4bf6248-c25e-4846-ab32-07f8b3e1cc4d&pf_rd_r=CCCNPE8M9DSCYZNGAW00&pd_rd_wg=k7dyo&pd_rd_r=e5c16519-1874-4b92-adcb-af857eab5508&ref_=pd_gw_ci_mcx_mr_hp_atf_m I'm not sure about it's powering. It works with USB C Power Distribution (PD), but I prefer just a simple 12V DC 5.5/2.1mm socket. I would buy it, but have other priorities now.

How to do it? Can I do it with masterBias files as well? For different cameras? 🙂

Thanks John for the tip regarding tolerance. I learn every day. 😊 There is also another way to add files with e.g. different exposure time by adding custom files. You can cheat a bit and declare that the files have other parameters then in fact they have.

I can recommend ASTAP if you are interested in free software. It can stack your all multi-night data with flats if you do them after each session. Be aware that flats allow shadow removal (related to dust on your lens/mirror or filter if you use any), so I can recommend doing them every time. Also, ASTAP offers plate solving and gives quite realistic colours.

The main part is called EL (electroluminescent) foil and I think you can buy it. There is also a powered from 12V power supply. This flat field panel sold by @steppenwolf looks like homemade, so ask him please for details. A few years ago I made a DIY flat field panel which I'm not sure if is fully OK for my 10" Newtonian. I made it using an LED kitchen ceiling lamp which is much different than the EL foil - the EL light is really flat.

The biggest flat field panel I ever had, thanks to steppenwolf. 🤩

Indeed, very nice picture. 😍

It happens to the Sigma as well, but I don't remember how much it moves. I'll try to record the values bot for the Canon and astro-cameras.

Am I right if I assume that any sensor tilt adjustment makes sense only if the camera is permanently attached to a rest of the setup and is never touched, particularly never rotated? Of course, I don't mean a case when the sensor isn't parallel to a flange and it 'accidentally' passed a QC which hopefully doesn't happen to more expensive cameras.

🙂 Yes, it has. It's always switched to the manual mode, even if used with the Canon body. I used a Bahtinov mask earlier, but now I rely on an EAF.

Apart from ASI224MC and ASI678MC with their total sensors surface smaller than a half of the APS-C ( 😁 ) I have also a 2600MM Pro which is permanently attached to a filter wheel and used with bigger scopes. I think I have no choice and have to (reluctantly) disassemble it if I want to perform a proper test.

I've never had any bigger problems with tilt on this camera. The only tilt-like effects are related to a bent and it's always visible on the edge aimed down during the session. Here is a masterLight as example with an Askar FMA230: The stars aren't perfect, but take please into account that my Askar FMA230 has its back focus equal to 52.5mm instead of 55mm, so I stopped selecting spacers at an acceptable point which is fixable by a BlurXterminator. Here is the same camera attached to an Altair 102 EDT Triplet APO with a dedicated x0.8 reducer, distortion is neglectable (at least for me).

Yes, I have a lot of thin plastic spacers starting at 0.2mm and also three paper ones, around 0.1mm each, I described experiments with them earlier in this thread. I reached a compromise between the coma and radially elongated stars at 1.2mm spacer in total, but I used filter then, I think it was the L-eXtreme. I have to check it again without filters, but not tonight, the setup is at home now due to clouds. I'm happy to see that the Sigma lens is OK, I considered returning it under warranty... There is a very interesting method of setting the iris permanently: Based on a following CN thread I attached the 6D body, set a BULB mode, pressed the shutter release button and... detached the body - the iris remains in the F/1.8 position. That's a great trick! https://www.cloudynights.com/topic/837147-sigma-art-40mm-14-canon-mount-no-aperture-ring/

There is not too much to measure, only the ZWO filter drawer. I base on the Sigma 44mm flange distance and the ASI 17.5mm back focus. The ZWO must be the remaining 26.5mm long and it is indeed. I use a high-class vernier caliper which is older than me. I love to use it, even if I have two digital ones.

Oh, yes, the lens is 1.3kg heavy, so I bought a dedicated ring holding it while the Canon or the ASI camera (both around 700g) is just attached to the lens. I wouldn't be worried if I saw marks of the tilt: pinpoint stars along one edge and comas on the opposite edge, but that's not the case.

Originally, I wanted to buy a 50mm lens. When I made some research I found that the 50mm lenses are as you wrote above. Then my attention focused on a Tamron 35mm and the Sigma 40mm Art. I had to read a lot to find that the Sigma is outstanding even at F/1.4, better than the Tamron. It's worth the price. I measured the optical path of the ZWO EF/M42 filter drawer using a vernier caliper.

I have to admit that I didn't think about it. But today I didn't use any filter.

I'm sorry, I don't understand. My full frame Canon 6d gives nearly pinpoint stars at F/1.4 while the smaller APS-C gives the coma. Shouldn't it be the opposite? BTW, I bought the 40mm F/1.4 Art with an assumption to stop it down to F/1.8 or F/2.0, if needed, but rather not to F/5.6.

Thank you, @michael8554, you inspired me to a more intense analysis. I realised that I used filters from the beginning which falsified the flange distance by mentioned 1/3 of their thickness (L-Pro Canon FF, 2" IDAS LPS-Pd and 2" L-eXtreme). I couldn't sleep well, so decided to remove the filters and any spacers and make another comparison with the picture from the CN thread (Canon 6D, F/1.4). The results are as follows. A starfield from the CN thread: My own Canon 6D at F/1.4 - that means it's the same setup: ASI 2600MC Pro with ZWO Canon EF/M42 filter drawer, exactly 26.5mm of an optical path + 17.5mm of the APS-C camera back focus = 44mm of the flange distance: I couldn't capture so many stars, but I would risk and say that my copy of the Sigma 40mm F/1.4 Art looks slightly better than the CN user's one. It's also possible that the difference is caused by an astro-modiffication performed on my Canon 6D. The question remains why the stars captured by APS-C are so distorted, although they should look better than with the full frame sensor. The goal is to use the ASI2600MC Pro camera with filters: IDAS LPS-P2 and Optolon L-eXtreme which make the distortion bigger. Enlarging the flange distance with spacers caused the coma to turn into radial elongation in some corners which seems to be a compromise. Is the ZWO EF/M42 filter drawer designed wrong? Or the camera back focus isn't equal to 17.5mm? I would appreciate any constructive conclusion.

Try to think about the astro-imaging as about an art: it's as good as you like it. You can observe others' work on AstroBin, save some pics matching your FoV, etc. and try to do your best. Of course, the PI isn't the requirement, the main product and the BlurX may become a game-changer if you really want them. You can remove stars and noise using free components, not necessarily StarX and NoiseX.

I don't know how other programs deal with it, PixInsight can do it. I would say that the remainder contains the software and the skills components. I know that talented imagers can use Siril and GIMP only to reach outstanding results, but modern and sophisticated software may help in the progress curve.

Well, indeed, I was focused on the noise reduction too much. I agree that the main object is blurred. I used a GeneralizedHiperbolicStretch which I still learn. BTW, I operate on the layers, process mostly the starless and use masks. I have to look deeper into the noise related to the stars layer.

Now it looks better and also didn't require so much stretching.

Imagine, how cheap is the ASIAir if you think about it's simplicity and functionality. It would cost like a StellarMate new product, but it doesn't, just because you have to buy their more expensive stuff. I think it's quite fair. Also, they tie you with their brand.