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Old 04-14-2009, 06:44 PM
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crunch crunch is offline
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Quote:
Originally Posted by sk66 View Post
Consider two lenses, same focal length and aperture. One lens is "tack sharp" at that aperture, the other lens not quite so sharp. The lens having difficulty with sharpness is due to diffraction errors. The light IS getting thru, but it isn't falling where it should in the scene. (To block the stray light and fix the problem we "stop down"). The result here might be that the "overall scene" appears lighter because the "stray light" is falling across the entire scene. It would also have less clarity/contrast for the same reason.
This is probably what's happening. However, I think we've entirely discounted the fact that a quality lens is "better" than a cheaper lens as it lets in significantly more light at the same aperture, shutter and ISO settings. This is simply not true and should answer the OP beyond any doubt.

Last edited by crunch; 04-15-2009 at 09:31 AM.
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