Re: [APML] M51 RGB (only)

[Jerry Lodriguss <jml@astropix.com>]

I want to applaud Tony Hallas and Rob Gendler for their recent posts.  If 
everyone , CCD and film shooters both, included this kind of detailed 
processing information with their posts announcing new pictures, everyone 
on the list would gain both knowledge and aesthetic pleasure.

Thanks guys.

Jerry


At 11:38 AM 4/21/2002 -0700, you wrote:
>Howdie folks,
>
>     So.... following Rob's lead, here goes: I have been putzing around 
> with color information via a CCD instead of film... guess what? Noise is 
> still enemy #1. So the same rules apply here that apply to film... shoot 
> lots of images and average. I gathered up all the bits and pieces that I 
> had on M-51 and did all the "reduction" process on them... this is the 
> same as cleaning up photo images by getting rid of vignetting, dust 
> spots, etc etc etc.
>     Then these files, all in 16 bit info, were imported into Registar to 
> average and merge into a 16 bit RGB. By combining the RGB before any 
> curves or post processing was done, the color balance as dictated by the 
> filters and exposure times should be pretty much "locked in."
>      Then I took the file into PS and gently applied curves and some 
> level corrections for the black end point to compress the data. I applied 
> a slight amount of saturation to the image. Basically that's it. What I 
> got, I think, is a pretty close approximation of the true colors of M-51 
> since this is "pure" RGB... no L, no nothing. Note that the little galaxy 
> at the bottom is very blue... active star formation or something, and 
> there is an interesting blue arm from the main galaxy near the 
> companion... in color you can see from this that M-51 is probably in 
> front of the companion which is a different color... in the 200" image 
> you can see this as a string of material from the main galaxy but it is in B&W.
>
> 
><http://www.astrophoto.com/M51RGB.htm>http://www.astrophoto.com/M51RGB.htm
>
>      Tony



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