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How to bring out the color out of H-Alpha, O-III, and SII files w/o Dark/Flat files?

Processing SHO Deep Sky NGC7000 NGC Objects
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miyan9 avatar
miyan9 avatar
Hello,

I was able to image several hours worth H-Alpha, O-III, and SII data, but I was wondering if anyone could suggest a specific method or program that will allow me to colorize these images once stacked, without any RGB or any Dark/Flat files. 

This is from NGC 7000, and this is what I have so far:

Screen Shot 2024-06-15 at 4.33.11 PM.png
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Quinn Groessl avatar
Quinn Groessl avatar
Whatever processing program you'd normally use. Pixinsight, Gimp, Pixinsight, Sirill, etc. You have to assign a filter to each R, G, and B. Usually it's Sii to R, Ha to G, and Oiii to B.

Here's a link to tell you more information about calibration files since it seems from your post it seems you're not sure really what they're for. One thing I’ll add because the article doesn’t mention it that I see is that you use either bias or darkflats, not both. Since your camera looks to have low thermal noise, I’d just go with bias. https://practicalastrophotography.com/a-brief-guide-to-calibration-frames/ Looking at your screenshot though, while not ideal, you should be able to get a nice image without them in this case.
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miyan9 avatar
miyan9 avatar
Quinn Groessl:
Whatever processing program you'd normally use. Pixinsight, Gimp, Pixinsight, Sirill, etc. You have to assign a filter to each R, G, and B. Usually it's Sii to R, Ha to G, and Oiii to B.

Here's a link to tell you more information about calibration files since it seems from your post it seems you're not sure really what they're for. One thing I’ll add because the article doesn’t mention it that I see is that you use either bias or darkflats, not both. Since your camera looks to have low thermal noise, I’d just go with bias. https://practicalastrophotography.com/a-brief-guide-to-calibration-frames/ Looking at your screenshot though, while not ideal, you should be able to get a nice image without them in this case.

I appreciate the link, Quinn. I didn’t look into those because I just wanted to get something under my belt (first narrowband imaging session). 

so I should go ahead and stack all SII data files and assign it to R, and so on, in order to get the colors going, right?

I’m definitely putting in the work for the calibration files next. I know they are important.
Rob avatar
Rob avatar
so I should go ahead and stack all SII data files and assign it to R, and so on, in order to get the colors going, right?


Yes, stack each filter's data separately.  Then you will be able to combine the three separate stacks to RGB as you wish, either as SHO, HSO, etc.
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