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troypiggo
09-03-2009, 12:21 AM
Playing around testing configurations the other night from home. Test target was Omega Centauri globular cluster. I was spoiled recently by imaging at a dark site. Home here is pretty heavy light pollution. Caused me some grief with white balance. Tried for hours mucking around with different methods trying to get the pink/orange vomit colour out of it. Ended up getting most out ok, but the stars still looked a little pink to me, so desaturated it :)

http://piggo.com/~troy/photos/2009/2009_03_06/omega_centauri_bw.jpg

spearo
09-03-2009, 06:41 AM
nice shot
tight stars and lots of 'em
frank

troypiggo
09-03-2009, 09:18 AM
Thanks Frank. Suspect I blew the core out a bit. Think I need shorter exposures. Next time - I've made notes in AstroPlanner (http://www.ilangainc.com/astroplanner/);)

iceman
09-03-2009, 09:20 AM
Nice work Troy. Can you post the colour versions so we can see what went wrong?

troypiggo
09-03-2009, 02:47 PM
Thanks Mike. This is the "original" light polluted version (scaled down):
http://piggo.com/~troy/photos/2009/2009_03_06/omega_centauri_orig.jpg

This is the best I could do with colour. I picked the colour of the background light pollution and painted that in a new layer and set the layer mode to "subtract". All the stars came out blue/cyan and the core was too dark. So I created a layer mask using a grayscale of the original shot, played with the contrast of the layer mask and got this. Result is that the bg LP is gone, but the stars have that vomit colour hue.
http://piggo.com/~troy/photos/2009/2009_03_06/omega_centauri_masked.jpg

strongmanmike
09-03-2009, 05:05 PM
That actually doesn't look too bad....nice work :thumbsup:

Mike