Re: Adjusting development for temperature

OK, I don't have the reference book for cold weather processing on-hand. It

must be in storage. Leitz had good information in one of their earlier 
books. I might find it this weekend.

In the meantime, an *authoritative source mentions the rule of thumb 
mentioned earlier - quoting from the book, "a general rule of thumb for
the 
range of 65 to 95F is that a decrease of 10F increases the development
time 
1.5 times." and they mention that the rule of thumb is just that - am 
approximation.

Note that they do not include temperatures below 65F because lower 
temperature solutions have more profound differences; they are not covered

by the rule of thumb.

* source: SPSE Handbook of Photographic Science and Engineering
1,416 pages