Mij Adyaw wrote:
> > An F9 lens will have better color correction than an F6 one.
> Is this really true for all scopes? The AP 130 F6 does not exhibit any
You may not see any, but it is there. It may be as small as 1 part in
20,000 (or whatever it happens to be), and you won't be able to see it
at the eyepiece in all likelihood, but it can be measured.
> Very short focal length high quality eyepieces are available and therefore
> it is not necessary to use a barlow.
Not necessary, but it might be harder on the pocketbook. :)
Brian Tung <brian@xxxxxxx>
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