Re: Telescope magnification question

"Mike Dworetsky" wrote in message news:TMmdna9OSIFmTUPaRVnyuQA@xxxxxxxxx
"Neil W" wrote in message news:47dec71e$0$25031$607ed4bc@xxxxxxxxx
This is really more an optics question, but I'm hoping someone here can
answer this question from an astronomy course and explain the reasoning.
Thanks!

A telescope has an aperture of 8", objective focal length of 80" and a
1/2" focal length eyepiece. What is the magnification?

Is this a trick question? Visual magnification is just the quotient of
the focal length of the telescope divided by that of the eyepiece.
Anyways you need to ask the instructor to come into the 21st century and
use metric measures.


Thanks for the reply. Nope not a trick question. At least not to a novice.
That means that the magnfication is 160"?

Incidentally, what is the meaning of the "objective" focal length vs the
just plain focal length?





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