Thread: ASTRO: NGC 2903
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Old March 15th 07, 07:05 PM posted to alt.binaries.pictures.astro
Rick Johnson[_2_]
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Default ASTRO: NGC 2903

Stefan and I imaged this guy about the same time. I had taken something
low in the sky just before and had set the blue exposure time to 7
minutes to compensate for the loss of blue low in the sky. I forgot to
reset to 5 when shooting this one. This means I got blue data in the
dimmer parts of the image that didn't show much color data at all in the
red and green images. Thus, the faint outer arms as well as the
companion to the east (left) came out too blue where really faint. I've
spent three days trying to fix it. Not being a photoshop expert it
hasn't gone well. I just have had my fill and posting where I'm at.
Think I have 2903 about right but the companion UGC 5086 has a red
center and blue halo I doubt is correct. Fixing that screws up 2903
unless I isolate it and adjust only one which I don't like to do. Other
faint galaxies show the same problem. LEDA 1648681 below 2903 is
another example.

Aladin says I picked up a QSO but it also says it is mag 20.9V. No way
this shot went anywhere near that deep. The star barely shows on the
Red POSS 2 plate though shows about like my shot on the blue. My
software puts it at 19.0 which looks right to me. So is the QSO hiding
behind a 19th mag star? It's B 0929+218 for those curious enough to
look it up.

14" LX200R@F/10, L=6x5' RG=3x5' B=3x7' all binned 2x2, STL-11000XM,
Paramount ME

Rick

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