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welly
9-Oct-2012, 19:29
Hi all,

As summer approaches down here, the cold water tap is beginning to warm up and yesterday water was coming out at 22c. I'm looking for some temperature compensation charts for developing TMax100. Does anyone know of any in existence or failing that, if anyone can give me some pointers? I'm currently developing TMax100 (at ISO100) in Rodinal at 1/50 for 12 minutes. Is temperature compensation generally fairly uniform throughout various films/developers? I could test it this evening but wouldn't mind a starting point!

Thanks!

Welly

SMBooth
9-Oct-2012, 19:39
I just keep some water in the fridge and regulate the tap water temp with that.
Here is Ilford temp chart

welly
9-Oct-2012, 20:05
Awesome, thank you. I'll try that out on some test film "just in case"!

And that's an idea about sticking water in the fridge. Or I could just use some ice cubes. Lachlan (I believe) was talking about using water at whatever temperature it comes out of the tap and compensating accordingly. He said he gets the same results at whatever temperature.

I think some time will need to be spent in the bathroom this evening.

Michael Clark
9-Oct-2012, 20:48
A warning about using ice cubes to cool the developer is that if the rest of the chemicals are at a much higher temp. reticulation could result. Here in southern California we have had a very warm summer and as a result I have run the developer at the same temp. as the tap water (about 75 to 85 deg. f.). Using Tmax RS and Xtol developers for film. !1;1 to 1;4 dilutions seem to work fine for me.

Mike

Cletus
10-Oct-2012, 04:31
I use ice cubes to bring the developer to temp in the pitcher, during the dilution process. Especially Rodinal, where the dilution is high, but I do this with all my film developer. My "cold" water in Dallas, TX in summer is closer to 32C and never had anything remotely close to "reticulation" issues. If I'm tray developing, I'll stick an ice cube or two into the stop and fix for good measure, but don't bother adjusting to exactly anything.

Also, FWIW, when tray (or tank) developing, if I get a liter or so of fresh water down to 20C to use for a prewash, just prior to developing, I find that developer temp does not tend to rise more then 0.5-1.1C during development. If I prewash the film in 30C+ water, it raises the developer temp as much as 2.5-3.0C during development.