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Old 17-11-2005, 01:46   #4 (permalink)
Gandhi
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Quote:
Originally Posted by SammyC
But as the focal length increases, the apature may stay the same in size but the ratio (f) will change.
Correct a mundo!

I think you inadvertantly answered you're own question james young man!

the maximum aperture of a zoom lens is always taken at the widest point of the lens. e.g. 35-420mm f2.8-f3.7. The actual aperture stays the same size, but as the zoom length increases so does the ratio.

I'm not sure if that is technicaly correct, but that's the logical conclusion based on your theory given above.

Last edited by Gandhi; 17-11-2005 at 01:50.
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