Paper developing temperature

[Fred Braakman]

When setting up my paper developer, invariably the temperature of my room and chemicals is always 1 to 2ºC below the recommended temperature. Is it necessary to warm the developer that 1º or 2ºC, or is temperature as important as it is with film developing? Is there a table available that allows you to compensate the temperature by increasing the time of developing for paper, as there is for film?

Fred

[fredthetree]

Look up "factorial development" -- something Ansel Adams describes in The Print. It enables consistent development even if you have variations in temperature and exhaustion of developer (the more paper you process in the same tray of chemicals, the longer your development times will be).

[Brian Ellis]

You might investigate the Zone VI Studios Compensating Developing Timer, which is designed to automatically adjust the time for temperature changes, increasing your set time as the developer gets warmer and decreasing it as the developer gets colder. I used one for many years and it seemed to work well even though different papers don't all respond identically to temperature changes. I don't know whether Calumet still sells these but if not they appear on ebay and other places occasionally.

[Oren Grad]

No, it's not as important as with film developing, because with film you get only one chance, whereas the worst thing that happens with a print that doesn't come out the way you wanted is that you try again with another piece of paper.

I've never bothered trying to control developer temperature for prints - I just let it drift with the room temperature. If I were producing large editions of prints that had to be absolutely identical across multiple printing sessions I'd worry about it, but I'm not, so I don't.

[robc]

you always develop paper to completion so the effect of lower temp just means it takes longer or higher temp means it takes less time. A couple of degrees either way won't cause problems providing you develop the paper for long enough.

[Kirk Gittings]

A degree here or there for paper is irrelevant, but do some testing with exposure and developement times and the subtle effects that you can get. While there is an effective "completion" around two minutes for various papers, there can also be benefits in terms of d-max and highlight separation at 4 to 6 minutes.

What I have done for years to combat developer exhaustion is to replenish the dev. For long printing sessions I mix up an extra batch and keep it nearby in a beaker. For every 4 8x10 or 1 16x20 I add an once. That amount seems to adequately compensate for absorbtion loss and depletion.

[Fred Braakman]

Kirk,
I like that idea of replenishing developer. How long can you continue to replenish the same batch of developer?
I notice that as developer is used, it will slowly turn yellow due to oxidation. Can the developer continue to be used in this state, even with replenishing?

Fred

[Kirk Gittings]

Fred,
I never kept track in that way. I do know that I have kept it going all day that way printing editions. I start out with a gallon of dev and replenish it consistently. I always try to start out in the morning with fresh chemistry, later when it seems I can't get the dmax I expect I will test a small dark area in a small tray of fresh dev, but usually that is not the problem.

[eric mac]

I was going through Fred Pickers notes this winter as my darkroom drops into the low 50's. He came up with the following times.

Using 68F @ 2 minutes as a base.

60F 3 minutes 28 sec
75F 1 minute 14 sec
80F 52 seconds.

I think his compensating timer is based on these points.

I read somewhere that the developer stops working below 60F. I ended up using 3 fish tank heaters in my trays to keep my chemistry at 70F (heater limitation).

Eric