>William writes:
>
><< Gary Reese has measured film reflectance, and I have a question for
him. As
>film is exposed to light, the silver halide slowly breaks down into
metallic
>silver (or undergoes other chemical changes). (You can see the darkening
this
>produces by exposing the "tongue" to light for a while before loading the
>film.) This change doesn't occur rapidly, but I was wondering whether Gary
>measures reflectance "promptly" after pulling the film from the canister.
>>
>
>You bet I accounted for that. I measured with a Sekonic 1 degree spot
meter
>on freshly exposed to the light film surfaces.
>Makes for a good argument to advance the film just prior to exposure.
That
>will result in more consistent (don't read accurate) OFT exposures.
err,
It shouldn't make a lick-spittle worth of difference, unless you've
got some light leaks in you camera.
duncan
(who's found that his OTF exposures are great for sensia & velvita@40
just the way they are)
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