I caught the eye of Princess Andromeda for a few nights up at AstroFest and also managed to catch all the nasty atmospheric conditions along with it. This is about half the data I captured, the rest is worse
Anyhow, I'm not wild about this, so wanted to put it out there for suggestions. What's the best way to handle stars? This image was processed without a star mask, and as there's also a bout of unsavoury gradient from one of the nights contributing to this data set. I've tried playing around in DBE and can't really get it levelled out Consequently, I've not stretched it as much as I would like too. Maybe it just needs more and/or better data?
Not much wrong with that, Dunk. What don't you like about the stars?
Sometimes I'll take shorter exposures for the star cores only, then combine that data with longer exposed data using the HDR Composition tool. Helps retain core data/colour when stretching.
Hey Dunk, that looks awesome! The contrast is great. I can't see anything wrong with the stars. I hear you about the gradients and seeing. I had to dump a lot of subs too.
Nothing wrong that I can see either Dunk. Great image. Dbe should be able to remove the gradient. In case u don't know, you can apply DBE more than once if it doesn't come clean after the first go just run it again while the sample points are in placee. I asume u ensured the sample points weren't ontop of any stars? Takes a bit of patience but is definately worth the effort to check each sample point before running it. Hope that helps.
Not much wrong with that, Dunk. What don't you like about the stars?
Sometimes I'll take shorter exposures for the star cores only, then combine that data with longer exposed data using the HDR Composition tool. Helps retain core data/colour when stretching.
Thanks Rod! The stars just seem a bit bloated at 100% because of the stretching, I just haven't found a star mask method yet that doesn't leave pandas eyes Good tip on the HDR, thanks for that
Quote:
Originally Posted by multiweb
Hey Dunk, that looks awesome! The contrast is great. I can't see anything wrong with the stars. I hear you about the gradients and seeing. I had to dump a lot of subs too.
Thanks Marc! Yeah I knew it would be a challenge being low and all, I guess we were lucky to have so many clear nights, even if they weren't perfect.
Quote:
Originally Posted by AstroJason
Yeah Dunk, like the guys have said, this looks great mate. Have you tried one of Carboni's gradient removal tools in PS? Might be worth a shot.
Thanks Jason! I hadn't tried it but I'll give it a shot
Quote:
Originally Posted by Rex
Nothing wrong that I can see either Dunk. Great image. Dbe should be able to remove the gradient. In case u don't know, you can apply DBE more than once if it doesn't come clean after the first go just run it again while the sample points are in placee. I asume u ensured the sample points weren't ontop of any stars? Takes a bit of patience but is definately worth the effort to check each sample point before running it. Hope that helps.
Thanks Rex! I guess I'm just pixel peeping, watching them grow with the drag of the slider I didn't think to run DBE multiple times, but I will try it again, thanks for the tip. Yeah I usually zoom in and check the sample points aren't on stars, nebulosity or galactic fuzz...especially tricky on this one as the fuzz was corner to corner.
I just haven't found a star mask method yet that doesn't leave pandas eyes Good tip on the HDR, thanks for that
I follow Juan's steps detailed in his post on the Pixinsight forum to produce a star mask Click here
If you find that some of the larger stars are not include in the generated mask you can use Range selection to select the larger stars, add some softness to the selected regions with its "softness" slider. Then use Pixel Math to add the Range mask and Star mask together to create your final star mask.
I follow Juan's steps detailed in his post on the Pixinsight forum to produce a star mask Click here
If you find that some of the larger stars are not include in the generated mask you can use Range selection to select the larger stars, add some softness to the selected regions with its "softness" slider. Then use Pixel Math to add the Range mask and Star mask together to create your final star mask.
Looks very smooth and detailed to my (admittedly less than expert) eyes Dunk. Very nice.
Compares well to my memories of the old Mt Palomar shots which first captured my imagination back when I was a teenager.
Thanks Pete! Glad to hear I'm heading in the right direction It's always hard to know what objects should really look like.
Quote:
Originally Posted by Rod771
I follow Juan's steps detailed in his post on the Pixinsight forum to produce a star mask Click here
If you find that some of the larger stars are not include in the generated mask you can use Range selection to select the larger stars, add some softness to the selected regions with its "softness" slider. Then use Pixel Math to add the Range mask and Star mask together to create your final star mask.
Works for me.
Great stuff Rod - thanks for that, I'll give it a go the stars are noticeably tighter in the raw files than the tickled result.
Hmmm that DBE seems quite effective here ...I always wonder if it is always accurate though, say when gradients are being removed from areas full of complex and faint galactic cirrus...? (and no I am not bagging PI ). I guess once you have its nuances and settings right and know what it can and can't do (like Decon/Wavelettes ) it's probably very powerful?
Nice Image. Here something you can try when using DBE. Make a clone of the image, then over stretch the clone image to see the gradient better. This will allow you to plot your point, more accurately. create a process icon then activate your main image. For the correction select "Division", this will flatten the image, also remove the color cast. Now select "subtraction" to remove/reduce the gradient. Subtraction can be used several time without degrading the image.
DBE is not a replacement for flats and won't get rid of imperfections like dust mots etc. But it does a pretty good job with gradients.
I'm jealous mate. You've got heaps of contrast in there. I'm gonna repro mine and try that DBE (hasta la vista gradients) thingy too.
Thanks Marc - between the two of us we must have some decent data you're welcome to add it to your subs, although it's only DSLR data
Quote:
Originally Posted by Brisbaneskys
Nice Image. Here something you can try when using DBE. Make a clone of the image, then over stretch the clone image to see the gradient better. This will allow you to plot your point, more accurately. create a process icon then activate your main image. For the correction select "Division", this will flatten the image, also remove the color cast. Now select "subtraction" to remove/reduce the gradient. Subtraction can be used several time without degrading the image.
DBE is not a replacement for flats and won't get rid of imperfections like dust mots etc. But it does a pretty good job with gradients.
Thanks Robin - I'll give it a try! It's quite a complex gradient, as Andromeda was scraping along the northern horizon, so it's the right hand side of the image that is the worst.
Makes me wonder if there is a way to remove the gradient in preprocessing I might be able to get away with rescuing a few more subs from the junk pile then.
haha I actually agree with Morton, I prefer the original Dunk, it just looks more natural. When you compare the two. The repro seems to have bloated the stars a little, seemed to reveal more noise and revealed a few dust bunnies or something towards the top of the image. That said, it has improved contrast and enhanced the fainter regions of the galaxy. If you never posted the original and just shared the repro I would still think it was a great image! That scope is killer!
I like the first version best. Admittedly I'm on my mobile just now so probably not seeing all the nuances. Very nice!
Thanks Morton!
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Originally Posted by AG Hybrid
They look fine. Stop whining Englishman.
Thanks Adrian! You miss the whining Englishman really
Quote:
Originally Posted by AstroJason
haha I actually agree with Morton, I prefer the original Dunk, it just looks more natural. When you compare the two. The repro seems to have bloated the stars a little, seemed to reveal more noise and revealed a few dust bunnies or something towards the top of the image. That said, it has improved contrast and enhanced the fainter regions of the galaxy. If you never posted the original and just shared the repro I would still think it was a great image! That scope is killer!
Thanks Jason! This is still a work in progress as I'm trying to rescue some additional subs, but it'll give me the opportunity to revisit the "look and feel"
Consequently, I've not stretched it as much as I would like too. Maybe it just needs more and/or better data?
I didn't think to run DBE multiple times, but I will try it again, thanks for the tip. Yeah I usually zoom in and check the sample points aren't on stars, nebulosity or galactic fuzz...especially tricky on this one as the fuzz was corner to corner.
It's always hard to know what objects should really look like.
). I guess once you have its nuances and settings right and know what it can and can't do (like Decon/Wavelettes 
) it's probably very powerful?
I might be able to get away with rescuing a few more subs from the junk pile then.
