[APML] Achromats?

["Blair Batty" <bbatty@nseaa.com>]

Relatively inexpensive achromats aren't used in
astrophotography because the various colours are
out of focus to each other (you know what I mean).

Why couldn't you use an achromat to take a photo;
focusing it sharply with one central colour (perhaps
using a filter over your eye so you only focus on 
one colour). Then:

1) Digitize
2) split into separate photos of RGB
3) Go into Lab mode and use the "in-focus" colour 
     as the L channel.
4) restack in registar
5) combine the original colour information with the
      "in-focus" L channel.

I admit I don't know what I'm talking about. But I wonder
if something like this would allow taking sharp photos
with a cheaper telescope? There are all those fast,
wide, inexpensive Chinese 'scope available now...

Sincerely
Blair Batty


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