[EMAIL PROTECTED] wrote:
> Example-- at ASA 200, the light meter jumps(fast) to positive when
> the shutter is set at 1 second. Similarly, the meter jumps positive
> at 1/15 sec with ASA 3200.
Mark Roberts <[EMAIL PROTECTED]> writes:
> Well, this has nothing to do with the film speed and and shutter
> speed being on the same knob, at least, not with respect to making a
> problem of this type more *likely*.
Yes, it does. It's a common enough problem. My MX has it, and it's
even documented in the manual. The thing is, that there is just one
potentiometer (variable resistance) in there, and turning the shutter
speed dial has the same effect on the potentiometer as does turning
the film speed dial within the shutter speed dial. Now, since the sum
of the angles each can be turned (1 to 1/1000 seconds and 32 to 1600
ASA on the MX being almost 270 and almost 180 degrees, respectively)
is greater than a full circle, it is simply not possible for all
combinations of shutter speed and film sensitivity to result in usable
metering.
In fact, on page 22 of the MX owner's manual, it says that the meter
works with shutter speeds from 1 at 100 ASA, 1/2 at 200 ASA, 1/4 at
400 ASA, 1/8 at 800 ASA, and 1/15 at 1600 ASA. When you think about
it, the direct correspondence between sensitivity and lowest speed
has to be there -- a doubling of sensitivity has to rotate the
potentiometer exactly as much as a doubling of exposure time does.
-tih
--
The basic difference is this: hackers build things, crackers break them.
-
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