Perhaps this question has been answered before. What would be the advantages of a short focal length telescope over a long focal length scope and vice versa. I presently have a celestron SE4 which is long focal length.
Thanks
differences in focal lengths
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Mike Hornstein
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Dick Jacobson
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Re: differences in focal lengths
Briefly, a short focal length gives you a wider field of view and a more compact telescope which doesn't vibrate as much, while a long focal length in general gives better optical quality. Your Celestron 4 SE is a Maksutov-Cassegrain and this design gives a short, compact tube while having a long focal length (f/13). So your primary advantage in going to a shorter focal length would be to gain a wider field of view. Opinions vary, but my personal view is that a focal ratio of about f/6 is the ideal balance between field width and optical quality.
30-inch homemade Newtonian with periscope
20-inch homemade equatorial Newtonian with periscope
14-inch homemade equatorial Newtonian
10-inch Newtonian that folds flat
6-inch Russian Maksutov-Newtonian on Vixen equatorial mount
Too many small scopes and binoculars to mention
20-inch homemade equatorial Newtonian with periscope
14-inch homemade equatorial Newtonian
10-inch Newtonian that folds flat
6-inch Russian Maksutov-Newtonian on Vixen equatorial mount
Too many small scopes and binoculars to mention
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Mike Hornstein
- Posts: 5
- Joined: Tue Jan 25, 2011 4:36 pm
- Real Name: Michael Hornstein
Re: differences in focal lengths
Thanks for the quick reply and for the good information.
Mike
Mike