Re: [APML] M13

["William R. Mattil" <wrmattil@ix.netcom.com>]

> Tony Hallas wrote:
> 
> Hello again,
> 
>      Someone has wondered why there are so many blue stars if a
> globular is supposed to be made up of only very old stars... really
> good question. First, my RGB color is "locked in" until it gets to PS
> as a 16 bit Tiff file so there is no way that I can think of where the
> colors could be altered. I checked Bill Fletcher's tricolor shot on
> his web site that he took with a 16" f/4.5 scope and where his stars
> are not washed out, they are blue, so does anyone else have a reliable
> tricolor shot of M13? Maybe the idea that a globular is made up of
> only old stars is suspect... would like to hear some feedback on this
> one if anyone else has taken tricolor that is not saturated.
> 

Tony,

As a follow-up, on page 224 is a color photograph of M15 and the author
states:

"The lack of striking color is due to each star image being overexposed
in its center and dropping off sharply to black background"

The picture in question was taken using Ektachrome 400ASA hypered using
a large 3.6 meter instrument. Upon close inspection though, the stars
have a orange hue to them. But first impression upon seeing this
photograph would be that they are white.

Best Regards

Bill


-- 
William R. Mattil	| Fred Astaire wasn't so great.
wrmattil@ix.netcom.com	| Ginger had to do it all backwards
(972) 399-4106		| and... in high heels.

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