developer temperature

[Chris Gittins]

The other night I printed some test strips of three varieties of Grade 3 paper: Galerie, Bergger NB, and Bergger CB. (Previously I'd always used VC, mainly Ilford MG IV.) I developed them in Photographer's Formulary F130. The F130 started out at 68 F, but it's cold in my basement. It's been very cold for the past several weeks and hasn't broken 60 F in the darkroom even with the space heater running full blast. (Not a big heater.) As a result, the developer cools over time. I try to keep the temp relatively stable by sitting mason jars full of hot water in the trays. With the mason jars refilled every half hour or so, the developer temp varied between about 66 and 71 F. My observation: the exposure scale of the paper, i.e., the effective paper grade, appears to be strongly correlated with the developer temperature. Although I didn't note the temperature at each strip was developed, I remember when I refreshed the hot water in the mason jars and the ES tracks the refills very closely. NB: Dmax didn't change, just the effective paper grade - varied from hard #3 to mid #5.

My observations seem consistent with Adams' comments in "The Print" re: temperature effects, but I'm curious to hear about other people's experiences. Are swings of over one grade for a 5 deg temperature change consistent with your experience? Controlling the darkroom temp would be a challenge. Any favored methods for holding developer temp constant? (Something better than a fishtank heater?) Do I need to invest in a temp control value and sit my developer tray in a constant temperature bath or is there a quick and dirty solution which will accomplish the same result at a fraction of the cost?

Thanks, Chris

[Nick_3536]

I use a fish tank heater for Ra-4. If it's good enough for colour shouldn't it be over kill for B&W? When I tested mine it held temps +/- 0.5C. That was in a picnic cooler which holds temps better then an open tray.

[wfwhitaker]

I think the best solution is the discontinued Zone VI compensating developing timer. Why Calumet decided to kill this product is beyond me; it's a godsend. They not-that-occasionally show up used or on Ebay. RH Designs has what appears to be a similar product, although I don't know if it offers the compensating capability of the Zone VI item.

Tempered baths are a possibility, but I'd look into a recirculating system. Otherwise I'd have to deal with the guilt (I live in California...short on water - I don't know about guilt) and the cost of dumping water down the drain.

[Mike Troxell]

I checked on the RH timer several months ago. At the time I checked, it did not have a compensating feature like the Zone VI timer but I believe they were working on a model that would use a compensating fuction. It might be available by now.

[Michael Veit]

During winter I place my developer on one of those food warming trays and that keeps the temp rock steady. The tray comes in handy even during the summer since certain toners work best at higher temperatures.

[Bob._3483]

Old style electric developing dish warmers come on the UK version of the auction site from time to time at low cost - don't know about your part of the world, but they are the simplest solution if you can get them.

Personally, I would invest in a bigger heater or partition off the darkroom area if the basement is large - that way *you* get to be as warm as the developer....

Cheers,

[Mark Sampson]

I use an oil-filled radiator to heat my darkroom- 600/900 watts, thermostaically controlled- that and having the water runing at 68F (or so) keeps the developer temp fairly steady. The last time I went to print it was 49F in the basement- it took awhile to warm up the darkroom but no trouble after that.

[Bruce Watson]

It's not just a matter of how long you have to keep the print in the soup. The lowered temperature can effect the results you get by changing the effective mix in multipart developers. An MQ developer, for example, will see less activity from the metol component as temperature falls. This has the effect of raising contrast as the development action comes disproportionately from the hydroquinone at the lower temperatures.

Without consistent temperature, it is difficult to get consistent results from the darkroom.

[Bruce Barlow]

My 8x10 developer tray sits inside an 11x14 tray into which I put about 2 quarts of water at about 74 degrees. The water bath keeps the developer at a constant temp, usually about 68 to 70, given that my stock solution starts out a little chilly, warmed up by dilution water. The total mass of the trays and water mean that its temp changes slowly. If I need to perk it up, I can replace or add to the water bath.

I love my Zone VI Compensating Timer, but I note that Fred made it to fit Dektol's time/temp curve (ditto HC-110B), and other developers may not respond (DO not respond) the same, so while I continue to use it, I use it with the water bath approach. I know there's a way to calibrate and use it more precisely with other developers, but I'm too lazy to do that. By the way, with Dektol I use it hot (maybe 75 to 80), and have wonderfully quick development times. Comparisons with "true 68 degree" prints show no difference from using Dektol warm, but the warmth in winter feels good on the hands.

[Daniel Grenier]

Solve those issues, and improve your work, by developing by inspection (DBI). No more worries about temperature, no need for compensating timers, no more mis-developed negs. A bit of a learning curve to it and a few items to buy (ie green safelight filter) but other than that, straight forward. Look up "DBI" or "development by inspection" on this site and/or http://www.michaelandpaula.com/mp/startframe.html (writings/development by inspection).