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here ya go Rohan. From "Astrophotography for the Amateur"
This is for 35 mm film, so there is probable a 1.5X adjustment for canon ccd
Focal length to field of view
400mm = 3.4 degX 5.2 deg
500mm = 2.7 X 4.1
600mm = 2.3 X 3.4
800mm = 1.7 X 2.6
1000mm = 1.4 X 2.1
1250mm = 1.1 X 1.7
1500mm = 0.9 X 1.4
2000mm = 41' X 62'
5200mm = 33' X 50'
3000mm = 28' X 41'
4000mm = 21' X 31'
5000mm = 17' X 25'
6000mm = 14' X 21'
8000mm = 10' X 15'
15000mm = 5.5' X 8.3'
20000mm = 4.1' X 6.2'
Now from what I understand if your using the canon then you need to multiply your FL by 1.5 to bring it inline with 35 mm film. This may mean you need to divide the fields of view to bring them into comparison. I'm sure someone else here would be able to make that clearer
Cheers
ps there is a formula for working it out if you have a different focal length, but its only withing 1% accuracy if your FL is over 1000mm
Field of View = 57.3 x (w/F) degrees, where w is the width or length of your film and f is the focal length of your scope. Again from "Astrophotography for the Amateur"
Last edited by [1ponders]; 13-06-2005 at 10:42 PM.
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