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camera FOV?

Started by Falling-leif, 10/08/2007 09:50AM
Posted 10/08/2007 09:50AM Opening Post
I just got my tracking mount working and I'm hoping someone on this forum can provide me w/ a formula.
How do you calculate your optical systems "prime focus" magnification and field of view. I've got a 120mm F5 (600mm) refractor and a NIkon 35mm camera. So I want to shoot some basic shots of some deep sky objects but I'd like to know what will (and wont) fit before I waste time and film.

Thank You,
Leif Edmondson
Boise Idaho
Posted 10/08/2007 01:13PM #1
Your camera will give magnification about equal to a 43mm eyepiece.

The diagonal measurement of your negative is about 43mm.

Change to a Nikon DSLR, (or any aps chip size dslr) and it'll be about like a 28mm eyepiece.
Posted 10/09/2007 10:00AM #2
The other answers are correct. But you might also try using the CCD calculator from Ron Wodaski