The photographer used a CCD camera at the prime focus of a 12.5" reflector telescope.
He made images as follows:
120 minute b/w detail scan.
10 minute red filter scan.
10 minute green filter scan.
20 minute blue filter scan.
By a technique known as "luminance layering" the photographer combined the images using Photoshop.
This gives the image detail, depth, and authentic hues.
For more information click the link:
robgendlerastropics
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To: MozartLover; Joan912; NovemberCharlie; snowfox; Dawgsquat; viligantcitizen; theDentist; grlfrnd; ...
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To: petuniasevan
12-1/2" diameter is getting up into the professional range of telescope sizes. Or a serious amateur in a good location with appropriate viewing conditions. The photographer has put a fair amount of time into his set-up, and possibly some money as well, although money can be replaced with labor to a degree.
To: petuniasevan
M81 bump! Thanks for adding me to the ping list! 
To: petuniasevan
Gorgeous!
9 posted on
06/20/2002 7:15:45 AM PDT by
Joan912
To: petuniasevan
I love these threads; they bring a sense of awe and wonder to my office for a moment!
I mean usually I just wonder why I came to work. ;^)
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