How do images differ in a telescope as the focal length differs?
Nick G asked:
Suppose that you have 2 telescopes with the same aperture, Telescope A has a focal length 3 times longer than that of telelscope B. How would the image size differ in telescope A from that in telescope B?
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Suppose that you have 2 telescopes with the same aperture, Telescope A has a focal length 3 times longer than that of telelscope B. How would the image size differ in telescope A from that in telescope B?
October 22nd, 2009 at 2:19 pm
The focal length of a telescope determines the magnification - all other things being equal…
Telescope A would have 3 times the magnification of B David D
October 25th, 2009 at 3:37 am
The image projected at the focal plane will be 3 times larger in telescope A. Through the eyepiece, you will get identical images if you use an eyepiece in telescope B with 1/3 the focal length of the one in A. injanier