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That's a very fine go at it David. I don't know if Photoshop is the same but when I opened the fits file in Gimp there were two seperate images, an rgb and a green version. I only used the rgb. When you say you used the Green chanel as a luminance layer was that the seperate green image?
Regards
Graeme
Hi Graeme, thanks. Your is good too.
Now when I open the fits in PS there is only one file. I saw you mention that earlier but have no clue what thats about
What I did here was to copy the mono image from the green chanel to a seperate document, worked on it to increase contrast and reduce noise then copied it back into the green channel. it is a technique explained well by this astrobackyard video. Although its on Photoshop I think it would translate easily to GIMP.
It is a really nice technique and can make great improvements - I have used it recently to remove red halo's on a l-enhance duo band image by doing star reduction on the red channel and it worked fairly well. I think I could make it better by taking a bit more care in getting but thats a Work in Progress!
That's a very fine go at it David. I don't know if Photoshop is the same but when I opened the fits file in Gimp there were two seperate images, an rgb and a green version. I only used the rgb. When you say you used the Green chanel as a luminance layer was that the seperate green image?
Regards
Graeme
Actually what I said above there was incorrect. in this instance what i did was after working on the green layer mono i copied it back as a new layer on top of the full image, layer blend mode to luminosity making this a luminosity layer based on the green channel - sorry about that. I'm not sure GIMP has a luminosity blend mode but i'm sure there will be a way to do it.
Re: AP Processing Challenge No. 4
Posted: Mon Jul 27, 2020 12:45 pm
by Graeme1858
Jockinireland wrote: ↑Mon Jul 27, 2020 7:55 am
Now when I open the fits in PS there is only one file. I saw you mention that earlier but have no clue what thats about
It must be a Gimp thing! I'll try opening as layers and use the green looking image as a seperate layer and see what happens. I'm not sure GIMP has a luminosity blend mode either, I'll have a play and get back.
Jockinireland wrote: ↑Mon Jul 27, 2020 7:55 am
Now when I open the fits in PS there is only one file. I saw you mention that earlier but have no clue what thats about
It must be a Gimp thing! I'll try opening as layers and use the green looking image as a seperate layer and see what happens. I'm not sure GIMP has a luminosity blend mode either, I'll have a play and get back.
Cheers for the video just going to watch it now.
Regards
Graeme
Hi Graeme,
I had a play around with GIMP and now I am even more confused. I have no idea what that lime green image is when you first open the fits. And then the "channels" show up as colour versions. even if i open a tiff. As you'll have seen from that video in PS channels are mono.
So I'm completely at a loss. Sorry!
Rgds
David.
Re: AP Processing Challenge No. 4
Posted: Thu Jul 30, 2020 1:57 pm
by umasscrew39
Jockinireland wrote: ↑Sun Jul 26, 2020 6:48 pm
i'm coming late to the party because i did not see the new system till today!!
Anyway, in photoshop;
Arcsin stretch
Gradient exterminator
A couple of general gentle stretches in curves and colour balance in levels
HLVG
carbonis local contrast
Carbonis lighten DSO
Noise reduction with Dfine2
selective high pass routine to bring structure to dark lane
Camera raw filter - slight dehaze, tiny bit noise reduction, pulled back the sat just a tad.
I then made a lum lllayer from the green channel as it seemed to have the best dust lane structure (in retrospect i probably should have done this earlier - like before the high pass sharpen. (well dang! I'll just need to try it again )
All bringing me to this...
This was great data to work with so thanks very much. I dont really think i've been able to do it justice.
Rgds
David
David........... glad you liked my data and thank you for doing a better job than me with it! I love the adjectives you use, 'slight', 'tiny', and 'tad'. Greta idea about the luminance layer from the green channel. I have never tried that. maybe I should reprocess it and give it a go.
Bruce
Re: AP Processing Challenge No. 4
Posted: Thu Jul 30, 2020 7:04 pm
by gcisko
I'm coming in really late to the party. But maybe better late than never.
I opened it in GIMP and adjusted the levels (within GIMP) to bring out the object from the black image. I then saved it as a TIF and opened and edited in Photoshop. The adjustments in PS was mostly levels and curves. But I did apply a AstroFlatPro filter to flatten it more, then I used TOPAZ Studio to remove some noise. I just started playing with Astronomy Tools Action Set, and made some basic adjustments there but nothing I can remember. Sorry.
I am really bad at photoshop and am learning how use it, especially for the assorted adjustments to get a proper color. So this was the best I could do. My focus was to try to bring out as much detail of the dust lanes as possible. Comments and any tips are welcome
Re: AP Processing Challenge No. 4
Posted: Thu Jul 30, 2020 7:34 pm
by Jockinireland
gcisko wrote: ↑Thu Jul 30, 2020 7:04 pm
I'm coming in really late to the party. But maybe better late than never.
I opened it in GIMP and adjusted the levels (within GIMP) to bring out the object from the black image. I then saved it as a TIF and opened and edited in Photoshop. The adjustments in PS was mostly levels and curves. But I did apply a AstroFlatPro filter to flatten it more, then I used TOPAZ Studio to remove some noise. I just started playing with Astronomy Tools Action Set, and made some basic adjustments there but nothing I can remember. Sorry.
I am really bad at photoshop and am learning how use it, especially for the assorted adjustments to get a proper color. So this was the best I could do. My focus was to try to bring out as much detail of the dust lanes as possible. Comments and any tips are welcome
Well I'd not call that bad at all. Really nice structure in the gas lanes and a nice level of stretch.
My only comment would be that it seems to have a bit of a green cast. I threw your jpeg through HLVG and it came out like below. Which now has a dirty brown cast But i think if you used HLVg earlier in your process you could end up with something different. HLVG is really great and I run it nearly every process as soon after initial stretchin as I can, and most of the time it improves things - even if you dont actually see the green cast starting out. Its free so give it a go. http://www.deepskycolors.com/archivo/20 ... Green.html
But I'm still very much beginner myself so maybe others more experienced may have better ideas.
Re: AP Processing Challenge No. 4
Posted: Thu Jul 30, 2020 7:51 pm
by gcisko
Jockinireland wrote: ↑Thu Jul 30, 2020 7:34 pm
Well I'd not call that bad at all. Really nice structure in the gas lanes and a nice level of stretch.
My only comment would be that it seems to have a bit of a green cast. I threw your jpeg through HLVG and it came out like below. Which now has a dirty brown cast But i think if you used HLVg earlier in your process you could end up with something different. HLVG is really great and I run it nearly every process as soon after initial stretchin as I can, and most of the time it improves things - even if you dont actually see the green cast starting out. Its free so give it a go. http://www.deepskycolors.com/archivo/20 ... Green.html
But I'm still very much beginner myself so maybe others more experienced may have better ideas.
I didn't try the plugin you mentioned yet. But I did go back and readjusted the RGB balance and then cropped it. Maybe this is less green?
Jockinireland wrote: ↑Thu Jul 30, 2020 7:34 pm
Well I'd not call that bad at all. Really nice structure in the gas lanes and a nice level of stretch.
My only comment would be that it seems to have a bit of a green cast. I threw your jpeg through HLVG and it came out like below. Which now has a dirty brown cast But i think if you used HLVg earlier in your process you could end up with something different. HLVG is really great and I run it nearly every process as soon after initial stretchin as I can, and most of the time it improves things - even if you dont actually see the green cast starting out. Its free so give it a go. http://www.deepskycolors.com/archivo/20 ... Green.html
But I'm still very much beginner myself so maybe others more experienced may have better ideas.
I didn't try the plugin you mentioned yet. But I did go back and readjusted the RGB balance and then cropped it. Maybe this is less green?
Personally I think that looks much better. Well done!
But what do you think? If I've learned one thing it is that for every five astroimagers you'll get 7 opinions. So you should go with your own tastes as much as possible.
Re: AP Processing Challenge No. 4
Posted: Fri Jul 31, 2020 6:43 am
by Graeme1858
Nice go at it Gcisko.
I usually deal with the Green cast by raising the Red and Blue levels. There's a choice of Shadows, Mid tone and Highlights. Shadows deals with the background.
When you open the fits file in Gimp there's a few options to select, the default is Grey Scale (I see where your 5 files comes from now!). I always change to Naxis 3 for RGB.
Regards
Graeme
Re: AP Processing Challenge No. 4
Posted: Fri Jul 31, 2020 3:08 pm
by gcisko
Jockinireland wrote: ↑Thu Jul 30, 2020 7:58 pm
Personally I think that looks much better. Well done!
But what do you think? If I've learned one thing it is that for every five astroimagers you'll get 7 opinions. So you should go with your own tastes as much as possible.
After checking this a bit I do think the adjusted image looks better than the greenish hue image. Thanks!
Re: AP Processing Challenge No. 4
Posted: Sun Aug 16, 2020 7:10 am
by Graeme1858
AP Processing Challenge No. 4 is now closed.
Thanks to Bruce (Unmasscrew39) for the data, greatly appreciated.
The next one is AP Processing Challenge No. 6, starting today, which will be a chance to have a go at processing an image of Comet 2020 F3 Neowise with data submitted by Greg ([mention]gcisko[/mention]).
If anyone would like to submit some data for a future challenge please send an email with a cloud storage download link to tssapchallenge@theskysearchers.com
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