APP Final Processing Stages

Processing Deep Sky Help Needed
13 replies•296 views
schmaks avatar
schmaks avatar
After I get through the stacking process and onto the tools piece (cropping, vignette, light pollution, HSL)—I am at a loss. I am more or less guessing and checking but need some direction.

Are there any good tutorials out there that you can share?

I feel that my subs and stack look good but then I end up destroying the photo in the processing portion.

Thanks!
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Uri Abraham avatar
Uri Abraham avatar
Hi,

The Astro Pixel Processor website is full of video presentations and tutorials.

try https://www.astropixelprocessor.com/video-tutorials/
schmaks avatar
schmaks avatar
Uri Abraham:
Hi,The Astro Pixel Processor website is full with video presentations and tutorials.

try https://www.astropixelprocessor.com/video-tutorials/


Thanks!

I think my issue is the fine control to pull out details/colors especially as it pertains to my wide field shots.
schmaks avatar
schmaks avatar
I do think that part of my frustrations are coming from the fact that the first clear nights since my telescope arrived were 95-100% full moon. I'll be curious to see how my data processed when the moon isn't so bright.
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schmaks avatar
schmaks avatar
Okay—here's my image of M81 and M82. This has been stacked in APP, cropped, removed light pollution, and calibrated background.

I keep running into issues processing this one. Any insights into settings/processes for the next steps of calibrating star colors, HSL selective color, and stretch settings, etc. would be greatly appreciated.
matthew.maclean avatar
matthew.maclean avatar
From the Whirlpool image you've posted, can we assume you are using a CLS filter here too? Shooting during the week up to the full moon when it is very high brightness makes it incredibly difficult to get any useful broadband imaging (even with a CLS filter). I usually don't even bother going out at all.

But it does look like either the calibration didn't work right or the gradient removal (or both)? The odd light and dark regions combined with striping looks strange (obviously). What does a single representative light frame image look like before stacking and calibration and all that? Any chance you have a few bad light frames getting integrated in if you examine them individually?

It may be that you will get a better result in the next couple weeks now that the moon is waning though.
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schmaks avatar
schmaks avatar
I’ll re check my frames to see… they seemed very even but I’ll double check in case I missed something.

I did indeed use a light pollution filter.

Just got the telescope and and first clear skies so I had to try.
Rich Sky avatar
Rich Sky avatar
If I may,
major field rotation, at least 10 degrees left border of image and NE corner of image. Guiding will fix that…
Clear skies
schmaks avatar
schmaks avatar
Rich Sky:
If I may,major field rotation, at least 10 degrees left border of image and NE corner of image. Guiding will fix that...
Clear skies


You may.

Looking forward to upgrading to a guided system.
Rich Sky avatar
Rich Sky avatar
these artifacts (Stacking borders) if not cropped, can really  change the colour palette of an image.
schmaks avatar
schmaks avatar
Rich Sky:
these artifacts (Stacking borders) if not cropped, can really change the color palette of an image.


Thanks, Rich—I was thinking to keep as much info while processing then crop after but with what you said, I'm assuming I should do my crop to where it'll more or less be before a lot of the color processing?
Rich Sky avatar
Rich Sky avatar
yes, that is correct, before the stretch. try it and let me know.
Clear skies
schmaks avatar
schmaks avatar
Rich Sky:
yes, that is correct, before the stretch. try it and let me know.Clear skies


That helped a bunch, Rich! I was able to pull out a little more detail and such. Given it was practically a full moon, I'm happy with it... good practice.

Now I am looking forward to clear dark skies.
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Ian Dixon avatar
Ian Dixon avatar
Great thread.  I just read through it and its very helpful.

Ian
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