Re: Magnification needed to split tight doubles

On Thu, 29 Jun 2006 15:54:27 -0700 (PDT), brian@xxxxxxx (Brian Tung)
wrote:

There is a secondary issue--a poorer scope will produce a more inflated
PSF. Two of these close together will be harder to separate at a given
magnification than those in a better scope.

No argument that for most people, increased magnification will make it
easier to split close doubles. But I don't think I agree that this is
more true when the images have increased overlap because of poor optics.
If anything, it's possible that double stars in a poor scope will be
_easier_ to detect as doubles, since the an oblong blob (not fully
split) may be noted at lower magnification than two very close
pinpoints. In any case, I was just pointing out that the resolution a
telescope can deliver is purely a function of its objective, and the
eyepiece (and therefore magnification) isn't part of that, except when
considered along with the resolving ability of the eye (which I think is
basically what you said earlier).

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com
.

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