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cuivenion

RGB M27 reprocess with Straton

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This is a reprocess of my M27 from earlier in the year. I discarded quite a few questionable subs and ended up with 90 minutes of 8 second subs.:

Scope: Skywatcher 200p

Imaging Camera: ZWO ASI224MC

This is the original image:

1079764683_Autosave0InternetICC.jpg.2faa4bb3c271efa6172d5749f543763f.jpg

I decided to check out Straton star removal and process the stars and nebula seperately using Pixinsight. Here's the reprocess:

Image65ICC.jpg.b84c97f2b6ef671bd3e639adf610a1c3.jpg

I went through a few versions before I chose this one. The processing experience was very different, after DBE there was no headroom with the black point and it was hard to get the background looking right. I think I got there in the end though. Let me know what you think, is it an improvement?

Here's the nebula without stars, its a little different from the final image, I pulled the stretch back a bit for the final version:

1374261925_NoStars.jpg.03e449c775981d5230d6bf403c9439d2.jpg

 

Here's the corrected version. The reprocess had the stars in the wrong place due to a cropping error:

Final.jpg.9293944766a87954e8f6c227996e162a.jpg

 

Edited by cuivenion
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I like the colours in the second one, but the nebula looks over cooked to me. It's better than the 'no stars' nebula, but still looks pushed too far.

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It looks good to me, the Ha regions are much clearer than the original image.

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Cheers guys, does over cooked mean too hard a stretch? This is one shot colour by the way.

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Aaargh just noticed the stars are out of position in the reprocess. I'll repost a correction when I get a chance.

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20 hours ago, cuivenion said:

Cheers guys, does over cooked mean too hard a stretch? This is one shot colour by the way.

Yes, you're correct. Just my opinion, as I've done exactly the same thing with some of my images trying to squeeze out too much detail.

It's still a great image, especially for only 8" subs!

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21 hours ago, cuivenion said:

after DBE there was no headroom with the black point

Use the check box normalization in the section for Target Image Correction. This way DBE doesn't alter the median background level of the image.

Then use background neutralization to get a neutral background.

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3 minutes ago, wimvb said:

Use the check box normalization in the section for Target Image Correction. This way DBE doesn't alter the median background level of the image.

Then use background neutralization to get a neutral background.

Thanks I'll give it a try. I've been wondering if I can run the image through Straton after cropping and DBE which would solve the problem but I'll try both.

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On 30/11/2018 at 16:55, wimvb said:

Use the check box normalization in the section for Target Image Correction. This way DBE doesn't alter the median background level of the image.

Then use background neutralization to get a neutral background.

Hi, unfortunately this didn't work. There was was no change in the image when normalize was ticked. I managed to get some black point headroom back when combining the stars and no stars images in PixelMath. I used the rescaling options. 

The corrected image is added at the end of the original post. Quite happy with the finished result so I think I'll mark this one as finished.:)

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