Is there some rule-of-thumb that is approximately correct for time/temp
correction for film- and paper developers or is every combination of
developer and film or paper? Are these curves continuous/monotonic
or "jumpy".
I am thinking about designing and building a temperature-controlled timer
in the spirit of the old Zone VI device. Their's was analog and I think
assumed a curve for D-76/Tri-X and Dektol/? for their correction.
I want to do this via a digital timer system but I'd like to avoid a
table lookup for each and every film/paper/dev combination. In a perfect
world, I'd only need one correction constant for film and another for paper
like Zone VI did. Failing that, I am contemplating having an adjustment
that allows the user to set the time-temp correction as a _percentage_ of
nominal @ 68F.
Thoughts and inputs welcome. The current generation of devices like the
PIC microprocessors and Raspberry Pi Zero make this sort thing really
attractive to do. There is a huge market of measuring devices out there.
I found a temp probe for the Pi that claims to be better than .5% accurate
across a very wide range of temps.
(Actually - as usual - the most expensive part of this would be the case,
hardware, and related things like sockets, power supply and so forth.)
--
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Tim Daneliuk tundra@xxxxxxxxxxxxxx
PGP Key: http://www.tundraware.com/PGP/
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