Re: [APML] Warm Weather Film Response-Or Lack Of It???

["westergren" <westergren@netzero.net>]

George and Kent,

When I did my lab type film tests all the exposures were done at room
temperature, which means 70° to 80° during exposures up to 4.5 hours.  I
guess I have the most comprehensive reciprocity film tests for astrophoto
use, much longer than Kodak ever considered.  I have not tested for the
temperature effects on reciprocity.  I have heard that cold cameras were
useful before hypering came into vogue, but I have never used one.  I
expressed a concern a year ago about hypering at 50°C.  A lot of us have
hypered with no observed color shift.  Jim Janusz told me about experiences
with film stored in hot cars where there was significant color shift.  Of
course Kodak recommends storing film at moderate, not hot temperatures.

In Kent's case, the lower sensitivity could be humidity or temperature, or
both.  Right now I doubt we have enough information to tell for sure.

Don


> Hi Kent
>
> I remember Terry Dickenson saying something about E-200 gaining the
> equivalent of a full F stop when used at temperatures below zero C, it
> could well be that at higher temperatures (+80F) that the reverse is
> indeed happening.
> When the film tests were done by various members of the list were they
> done in airconditioned comfort or in typical shooting conditions? I
> realize that this will vary a lot as those of us north of the 45th view
> -10C as comfortable...
>
> George Anderson


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