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Orion widefield

Posted: Tue Mar 16, 2021 11:02 am
by Sidartha
I am not happy with the result than I get...any help? thanks
60lights 1600iso 120sg
30darks
40bias
30 flats

https://www.dropbox.com/s/btp9604fd7yok ... m.jpg?dl=0
https://www.dropbox.com/s/sxhqqjebuxjg4 ... d.fit?dl=0

Re: Orion widefield

Posted: Thu Mar 18, 2021 1:00 am
by admin
Hi,

Would you be able to be more specific as to what you are not happy about and/or where things go wrong for you?

Are you sure you followed best practices with regards to data preparation? The dataset looks color balanced and possibly already has some sort of gradient removal applied. The gradient signature looks almost circular too, which would indicate a problem with your flats (unless you are definitely surrounded by very nearby light pollution domes in all four corners of the image?).
There are some strange artefacts (diagonal streaks) hidden in the top right corner as well;
Selection_509.jpg
Selection_509.jpg (50 KiB) Viewed 1243 times
Any idea where they might have come from? (are they foreground terrestrial objects maybe?)

It is extremely important you give yourself (and StarTools) the cleanest, best possible dataset you can. Otherwise you will just spend most of your time working around issues that keep changing every time you go out. This can get frustrating quite quickly (unless you like that sort of stuff of course).

Widefields are already tricky to process, and the odd gradient, pre-color balancing and odd artifacts make it even more so.
In this case, because you will have to open this color balanced dataset with the first option, you can use the Entropy module's Visual Ha preset (before color calibration) to bring out the loop, do color calibration, and then use the Super Structure's Dim Small preset to tame the busy star field (use a small Airy Disk Radius as this is an extreme wide field).

Highlights show some color aberrations (possibly due to lens used, possibly due to the pre-color balancing). Be careful when shrinking stars on widefields like these; there is not much background to help the algorithm draw from.
r_pp_LIGHTS_stacked.jpg
r_pp_LIGHTS_stacked.jpg (491.57 KiB) Viewed 1243 times