NGC 7023 - Iris - 2020-03-31

[discardedastro]

Another "what can I do in a night?" job.

Tried a few new things in post for this one, and in capture - captured in batches of 5 per filter with a few extra L batches, worked pretty well with the Baader filters all being parfocal. This was all on the 200P, ASI183MM-PRO, as per my usual. LRGB only, no Ha.

The processing for this I stuck broadly to form on - but I stacked L, R, G, B and then stacked those stacks to form a super luminance. I then did denoising and then per-master deconvolution with a RangeMask as usual, and used the PSFImage script to come up with the PSF (which worked really well - amazed something like this isn't in PI natively).

Then I did channel combination, denoised again, LRGB combination, the usual tidying up and whatnot. Quite happy with the result for a mere few hours of exposure - tried to pull more detail out in the centre, but didn't manage much without it looking a bit odd, so left it. The dust and clouds I can't pull more out of without more exposure time I think. Still quite a pleasing result I think.

[MarkAR]

Super image, want to have a go at this one myself. Just waiting for a clear night and hoping I can get my setup working correctly.

[cuivenion]

Hi, it's a good image but I've noticed there's black dots all over it when you look at it full size. It's making the image grainy and if that effect can be removed it'll look a lot cleaner.

Is it possible your darks aren't matched? Or is the range mask not providing enought protection during deconvolution? My advice would be to use the wavelets settings to protect the background instead of the range mask.

[discardedastro]

6 hours ago, cuivenion said:

Hi, it's a good image but I've noticed there's black dots all over it when you look at it full size. It's making the image grainy and if that effect can be removed it'll look a lot cleaner.

Is it possible your darks aren't matched? Or is the range mask not providing enought protection during deconvolution? My advice would be to use the wavelets settings to protect the background instead of the range mask.

Yes - I tried to fix these but I think I had a sequencing error with when I applied my denoising and so didn't denoise near stars. I was doing the processing ad-hoc during my workday in breaks, need to have another go properly focused on things.

I've struggled to have good results with wavelet regularisation/noise reduction settings as a means to protecting backgrounds, though doing a gentle MLT denoise pass first helps somewhat. Range masks help a lot, especially on RGB masters where there's a lower SNR and more background noise.

[Rodd]

Very nice.  Drop the brightness in teh core and you will be rewarded.