From: "Dirk Wright" <wright@xxxxxxxxxxxx>
>I've been able to observe the former by aiming a lens at a known,
unvarying
>light source and taking TTL meter readings at maximum and minimum
focus.
>Sure enough, some light loss was noted with some lenses.
>
I think all you are seeing with this measurement is the fact that the
lens elements are farther away from the TTL sensor at minimum focus. In
other words, the typical light fall off from extending the lens.
Be seeing you.
Dirk Wright
Okay, but isn't this the same as a decrease in effective aperture? Or is
there some other phenomenon going on here that I'm misunderstanding?
After 30-some-odd years of photography you'd think I'd know all this stuff
but, hey, I just takey pitcher.
---
Lex
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