I'm gonna do some experiments with this lens (a Vivitar 20/3.8) before
venturing into deeper waters with a Zuiko. I'll need to rig it up as
accurately as possible relative to a suitable flat plane (brick wall or
something similar), record the exposure settings, then repeat a few tests
with the film plane slightly askew to see how it affects the corners.
Maybe I'm too picky, or maybe this lens is simply flawed, but if this
represents typical performance of ultra-wides I'll probably stick with
nothing wider than a 24mm.
-----------
Lex Jenkins
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Musta been a UFO. It wuz flyin' an' I dunno whut it wuz. - A "farmer"
======================================================================
From: "John A. Lind" <jlind@xxxxxxxxxxx>
Date: Wed, 11 Oct 2000 19:15:50 +0000
One additional thought on this:
In a rectilinear lens (maps a flat field in critical focus to a flat film
plane), dead-center on the lens axis is the closest point to the lens of
the flat field in critical focus. [As I understand it, the focus markings
are for the axis, not the corners.] As you move off-axis the distance
grows. The corners are farthest away. The wider the AOV, the greater the
corner distance compared to the axis distance...
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