Why doesn't this make sense?
You are assuming I am interested in ultimate resolution. What happens if I want to make a wide angle image of the milky way? Or what happens if I want to do a survey for Asteroids, comets or nova? I'll want the fastest focal ratio practical.
Aperture, focal length and the ratio between them are all important factors.
Terry
Quote:
Originally Posted by Terry B
This makes no sense.
Optical physics states that resolution is proportional to diameter of the scope.
You need to compare your 500mm fl F10 scope ie 50mm diameter with the same scope with a focal reducer on it as this is what people do with their scopes ie a 50mm diameter f2 scope with a fl of 100mm.
I think I would rather use the 500mm fl scope rather than a 100mm mild telephoto lens.
If this is the case why do we bother with telescopes at all?
Just look at the sky with a camera lens.
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