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View Full Version here: : Images from a small verses large scope.


Daveskywill
09-07-2010, 12:51 PM
Hello everyone:

I was wondering: is it true that an image in a small telescope looks large and the same image in a large telescope looks small?

I thought that the magnification was determined by dividing the focal length of the objective by the focal length of the eyepiece. Also by dividing the apparent field of the eyepiece by the true field of the objective.

And isn't if that one item (magnification) that will determine how large the item will look in the eyepiece.

Thank you in advance for responding to this.
David

bmitchell82
09-07-2010, 03:04 PM
there will be others that pipe up on this one.

But it has not to do with aperature alone, I go by F ratios, where it is the focal length devided by aperature. hence the shorter your focal length generally the smaller but wider the field of view is. just the same if your focal length is long then your image will be big but your field of view small. hope that helps you a bit

higginsdj
09-07-2010, 04:24 PM
As a general rule, the larger the aperture, the higher the manification as there are practical limits to f ratios.

Cheers