Adam J

So to me it looks like a combination of some tilt and a little colimation error too, but not ideal images tp judge from as they look like they have not been bedayered? I would purchase an artificial star from FLO and have a play, its an invaluable tool when investigating colimation. Defocus (outside) until you have about 3 - 4 rings and then make sure the bright spot (caused by undercorrection in a fast apo) is in the center of the rings . https://www.firstlightoptics.com/other-collimation-tools/hubble-optics-5-star-artificial-star.html I can say its not entiarly a spacing issue. If it was the star shape would be out by the same amount in each corner. How old is it? Adam

Yeah got to agree, just grab the TS optics scope, the SW is still an unknown why take a risk on a new type when you don't need to? That being said I do like the SW brand. This is an example image, personally i would say it has a noticeable amount of blue bloat going on. https://www.astrobin.com/full/hecbjo/0/ Adam

Basically it comes down to if the objective lens is optically aligned correctly such that the centre of the optical axis passes though the centre of the corrector and intersects the centre of the imaging chip. This can be micro adjusted by placing a foil spacer on the red ring between the front objective assembly and the helical focuser. Ill provide a picture of mine if your image proves it relevant. Adam

i cant interperate that image, really need to see a star feild to give you an answer. What i will say is the colimation was not perfect on my scope and i had to tweak it. Tilt is possible also but really cant tell the difference without an image. Adam

Its not the scope, I have had a NASA APOD with the 130PDS. I did blacken the secondary edges, though I did not put anything over the primary end or flock it. Adam

just reading through this old thread, that will indeed be your problem. Adam

The issues with be import duty and servicing, I would go with a local shop with an established returns policy. Adam

They are all identical internally just some styling changes.

Looks good to me. Adam

Honestly I would no longer consider the imx183 as the best solution in terms of uncooled DSO imaging anymore. I assume you don't want cooled due to the budget. Why OSC? ASI533mm is or will be out soon. The ASI485 is out now and might be an better option for you. But if it was me I would go with the 533 once it's out, amp glow on the 183 makes calibration really hard for DSO imaging.

It will be fine for visual. I am less convinced for imaging.

The evostar performs well because it used fpl-53 in a doublet at f7.5, it appears to me that the evolux is a faster f-ratio scope with glass that is likely not in the very top end of available ED glasses (or it would be quoted as being one of them). So I have to be honest and say I would not be at all surprised if the evolux did not perform as well in terms of CA as the evostar. It's a scope with a different balance, better mechanics and faster f-ratio for imaging.

One of many issues I have with him is that he once made a video in which he listed a UV/IR cut filter as being a useless piece of kit. So who knows if he used one for that image. If not it would explain the apparently terrible correction though.

What are you planning to use it for and with what scope? Shockingly the fan cooling can make up to 7c difference in some conditions and so that's half the thermal noise. Adam

It's easier to control with a smaller aperture at the same f-ratio so you can't conclude anything about the 82 by looking at the 62. Adam

I would go with the Stellamira in this shootout you have no idea what glass is in the EVOLUX and I have seen blue bloat from it in images. Adam

From personal experiance, I would not go for the continual water feed from the tap solution as it will kill your water bill if you are on a metre. Adam

For some reason i have literally only just seen this. Sorry. Adam

You may not need to, but if you did I would use a rocket blower on it first, then once i was sure that no debris was on the surface that i could end up moving about and causing scratches I would then move to a 100% pure cotton but along side some Baader optical wonder fluid. You then need to keep swapping the cotton but out and repeating until no residue remains. Adam

Some smaller sensors power from usb only but the bigger sensors don't.

I believe that ATIK tend to use a quartz fused cover glass / window in place of a dew heater on most of their products.

Not quite. I would say dither and use darks. If the pixels are totally dead, dithering will result in the areas of the image covered by the dead pixels being statistically rejected from the stack. Darks won't solve totally dead pixels without dithering and sigma clipping or similar pixel rejection settings being used in the stacking software.

Sensor damage, possibly a cosmic ray as noted above. If under warranty you may be able to return it. Otherwise a large scale dither will help.

I think you may have missed low and got the double cluster instead of the heart and soul. Still a good first effort. Adam

Very good. One trick you might be missing is to take what you have here and then use just the full Ha data as a luminescence layer over the top of it, hence using the current image as a colour only layer. Adam