I just received the following comment from Mike Rhodes at Ti
Specialties, one of the companies that anodizes titanium.
"The anodized surface of Ti & Nb are actually very thin, only a few
hundred angstroms. Therefore I would not recommend anodizing a surface
that is subject to physical abuse as it will tend to scratch with time."
"I notice that the shutter curtain on my recently acquired OM4Ti has the
random checkerboard pattern indicative of off-the-curtain exposure
measurement. I was under the (obviously mistaken!) impression that when
the OM4Ti is not using spot metering, it uses off-the-film exposure
measurement. So, can anyone tell me under what circumstances the OM4Ti
measures light off the shutter curtain?"
For ambient-light exposures, all the time! The measurement _has_ to
begin the moment the shutter starts opening. Therefore, the curtain must
have a reflectance similar to that of film.
If this doesn't immediately make sense, think of what would happen if
the meter waited until the first curtain were completely open _before_
it started measuring. If the correct exposure were 1/1000, you would
nevertheless wind up with an exposure of about 1/60.
At the risk of offending those who went to the trouble of answering, I
must point out that the answers given about why small-format lenses can
(seemingly) supply higher resolution haven't answered anything. The
resolution of a smaller image does not necessarily scale with the image
size, and simply _saying_ that a smaller area allows for better
correction is tautological.
I'm still looking for an answer. If anyone finds it, I would be very
grateful. I'm going to pull out my Focal Encyclopaedia and Neblette and
do some searching.
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