Re: PHOTO-3D digest 1361

[P3D Gregory J. Wageman <gjw@xxxxxxxxxx>]

Neil Harrington writes:

>I, on the other hand, started shooting Kodachrome when I got separated from
>the service in 1953, and I bought a second-hand DeJur light meter to ensure
>that I got perfect exposures.  I followed that meter religiously.  And it
>was WRONG, gave me a lot of overexposed slides, which unfortunately I had no
>way of knowing until I got home and had the chromes processed.
>Irreplaceable shots, needless to say.  I'd have been a lot better off if I'd
>just read the packaged directions as my sister did years later.

Was it the meter that was wrong, or the camera, or both?

It's good practice to shoot a test roll or two with *any* new equipment
before using it to take irreplacable photographs.  I took my meter out
with all four of my (working) stereo cameras, all loaded with the same
film, and shot the same exposure on each.  I found that only the Realist
2.8 gave me my desired exposure at the indicated settings; all the others
were lighter than I liked (though not overexposed).  I haven't had the
shutters tested, so I don't know if I have three that are slow and one
that is correct, or one that is fast and three that are correct, but it
really doesn't matter because I know to compensate.

In case any of you are thinking it's the meter that's wrong, I checked
that possibility against my wife's Olympus OM1 bodies, one of which we
know is wrong (it reads high).  With the body that gives good exposures,
my meter and the Olympus agree exactly.  The body that underexposes
consistantly reads somewhere between a half-stop and a full stop too high.

Also, the field-of-view that the meter reads must be pretty closely
matched to the camera lens.  If you use a 40 degree attachment to meter
for telephoto work, you will get bad exposures, because you're metering
a different scene than you are photographing.  That's why TTL metering
was invented (and I guess the "zone system" too, but I don't know very
much about that...).


	-Greg


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