Wash water temperature?
Hi folks -
I just finished souping some Kentmere 400 in D76. Temperature was 66F, so I adjusted development time per a handy chart. They look good.
My question is: My tapwater measures about 54F. I seem to remember from chem classes ages ago that the speed of a reaction doubles with a 10C rise in temp, and halves with a 10C drop. Is there a need to adjust the wash time? It really isn't a reaction, but....any thoughts out there?
In the same train of thought, as I remember high tempertures may cause reticulation of the emulsion. While I've never seen any evidence of thermal damage cause by a temperature drop, might I be courting disaster by having a 12F drop?
Reticulation is difficult to achieve in modern film and a water temperature between about 25 and 30C combined with 10 or more changes of water will wash your film more quickly than 20 minutes of continuous running water at 20C. However, I don't do this, what's the rush?
Originally Posted by GRHazelton
Old fashioned reticulation still occurs with some films, and with others you'll still get problems. Wash at the same temperature as the rest of the process if you wanthigh quality results.
To be sure of avoiding problems I'd simply warm about 2 L of water to the same temp as the dev and use an extension of the Ilford wash sequence which is 5,10,15, 20, 15,10,5 inversions and dump.
Thanks, all! I think I'll just add a little warm water from the tap.