"Chris Taylor" wrote in message
...
Apologies for posting the second link twice, this was an afterthought.

The unprocessed image prior to digital enhancement.
http://homepage.ntlworld.com/taylor_.../M31unproc.jpg

The processed image
http://homepage.ntlworld.com/taylor_...31_resize2.jpg

Hope this demonstrates the rationale behind the application of digital
filters. I still hope to improve on these techniques someday. Its a lengthy
learning curve.

thanks chris, this is really useful. How did you remove the blue bias? In the processed image I
can still see a little blue gradient, but it's a fine image!
--
Martijn (astro-at-pff-software.nl)
10" LX200GPS-SMT
ETX105
www.xs4all.nl/~martlian