question about temperature control while dev

[kipkeston]

I cool my dilution to 20C before dumping it in but today I decided to take the temp after dev. After 9 minutes of developing it was 21.8C due to ambient temperature. I'm wondering whether I should be trying to control this and what kind of affect this may have.

 

[rlouzan]

I'm wondering whether I should be trying to control this
Yes

what kind of affect this may have.
Dense negs, blocket highlights, more grain, ...

 

[Keith]

I cool my dilution to 20C before dumping it in but today I decided to take the temp after dev. After 9 minutes of developing it was 21.8C due to ambient temperature. I'm wondering whether I should be trying to control this and what kind of affect this may have.

I have the same problem here in sunny Brisbane ... I actually put the developer in at 19deg to allow for this temperature rise during the developing cycle!

The other alternative I discovered was to sit the developing tank with the film in it in the fridge for about ten minutes or so before adding the solution to remove the effect of the higher ambient air temperature! 🙂

I supect with black and white it's not really that critical and the experienced darkroom curmudgeons would probably laugh at us for worrying! 😛

 

[hobbim]

I use a water bath for temperature control. (I keep the tank in water between inversions) It gives me better control. Sometimes I have 20C room temperature, sometimes 24C. With long developing times (15-20min typical) that makes the developing temperature vary a lot.

It is a matter of how repeatable results you need. If you constantly have it warm up similarly the results may be very repeatable. If the room temperature varies a lot it is not that repeatable.

You have now the developing temperature of 20,9C on average. If you keep it at 20C you'll have to increase the developing time a bit for the same results.

 

[Bryce]

I'll agree, you do want to control it for the reasons stated above.
The usual way is rather elaborate, difficult and costly: the developing tank and chemical containers are kept in a pan of water at the desired temperature. If the tempering bath becomes too warm or cool, water is added to bring it back into line.

 

[rlouzan]

Plastic or metal tank?

Solutions: Control temp, cut dev. time, two part dev. or find new EI

 

[kipkeston]

thanks. i'll give those ideas a shot.

it's a plastic tank but I've considered switching to steel. I live in hawaii, the temp is rarely near 20C, usually 25+

 

[oscroft]

Here the room temperature is a usually few degrees lower than 20C, so I start with developer at about 20.5C - it generally drops about 1 deg during development. But the absolute temperature isn't really that important - all you really need to do is be consistent and adjust your development time to suit those consistent conditions.

 

[Roger Hicks]

I always allow for drift, taking account of ambient and temperature 'in'. Either use a different 'in' temperature or vary the time.

But the truth is that like everything else in photography, you can get too excited about it. Overdevelopment does indeed imply more grain and more contrast -- though very rarely blown highlights, because most photographs use only the lower part of the D/log E curve, well before it shoulders off. The extent to which any of this happens with even a 2 degree rise over 10 minutes is surprisingly small.

Cheers,

Roger

 

[bsdunek]

Here the room temperature is a usually few degrees lower than 20C, so I start with developer at about 20.5C - it generally drops about 1 deg during development. But the absolute temperature isn't really that important - all you really need to do is be consistent and adjust your development time to suit those consistent conditions.

IMHO this is the best solution. I try to develop at whatever the ambient is and adjust times accordingly. That way there is no drift. If ambient is too far off then I use the water bath method. Rarely needed here in Michigan.

 

[kipkeston]

Normally I do Tri-x in xtol 1:1. That's 9 minutes essentially. If I wanted to take into account a temperature drift of 22 or 23C, would cutting somewhere around 30 sec to 1 minute be a solution?

 

[MartinP]

If room temp is more than a few degrees off 20 C then i just stand the tank and beakers in a washing-bowl of water at the right temperature. Having a few litres of water, that doesn't change temperature so much, makes for a more consistent result.

Temperature compensation graphs are usually available from the manufacturers of the developer, and probably even on the details-sheet that came with the developer.

 

[kipkeston]

Well, I've thought about putting it in water between agitation, but the water out of my tap is about 25C and cooling that is another cumbersome issue.

Is everyone developing b/w overcoming this issue with ease?

 

[MartinP]

An effective cooling method is to put ice-cubes in a plastic bag, then put the plastic bag in the water (or even developer, if you get desparate, though take care to avoid contamination). The bag can be swished around and easily removed at the appropriate moment - which cannot be said of a dozen loose ice-cubes floating around . . .

Alternatively, put a big jug of water in the fridge several hours before you plan to do any development. Then use that to mix with your "hot" cold-water.

 

[rogerchristian]

One consideration may be to prewet the film and accomplishing tempering to near 20C at the same time.

The Unicolor film drum recommended a prewet/heat which worked well since the drum ran on a roller motor so it started a couple of degrees high and with 'drift-by', it averaged the correct temperature. It had an insulating jacket which helped maintain temperature more easily than standard plastic or stainless tanks.

Plastic is a poorer conductor of heat and so may hold he temp a bit better, but with the better thermal transmission of the stainless, it may be easier to maintain a temperature in a water bath. I used to hand shake E4 and later E6. I learned to live/work with/love water baths!

 

[troym]

Well, I've thought about putting it in water between agitation, but the water out of my tap is about 25C and cooling that is another cumbersome issue.

Is everyone developing b/w overcoming this issue with ease?

Two options:

(1) Develop at a higher temperature. I'm pretty sure that Kodak publishes development times for Tri-X in XTol 1:1 at 24C (try searching their website). 24C is pretty close to your ambient temperature, and therefore that should minimize temperature drift during development.

(2) Buy a small styrofoam cooler and a reusable gel icepack. I use a fishing bait cooler, which is smaller and shallower than the standard beer cooler. Because styrofoam is such a good insulator, the cooler makes a great water bath and keeps temperatures stable. Wrap the gel icepack in a plastic shopping bag (for ease of handling) and use the icepack to lower the water temperature to the desired point. Once the desired temperature is reached, you can pull the icepack out and develop away. This is how I handled development during summers when I lived in Washington, DC, and I found this method much easier than using ice cubes and such like.

 

[kipkeston]

Ok. I will give these ideas a shot. It's actually the ambient air during agitation that brings the temperature up. The ambient air can is usually 25C+ in Hawaii. It's when you agitate and expose all those molecules to the air. I like the cooler and ice pack idea. I will try that next I think.

 

[Bryce]

The tempering bath is very effective because water is very much better at absorbing heat than air is and because the tank spends more time in the tempering bath than being agitated. The method is effective in temperatures at least as low as 10˚C or as high as 30˚.

 

[minoltist7]

I adjust room temperature to 19-20 C, and place all my three cans with working solutions to the bowl filled with cold (19-20C) water.
After 10 min temperature stabilizes to 19,5-20,5 C. I usually don't care about small time errors, becouse I use diluted developer and adjust processing time to 13-14 min to get more consistent results.
In the summer I'll adjust processing to 24 C

 

[DGA]

I use the cold water container trick for maintaining the 20C temp, but I somewhat made the process easier:
Here, the ambient water temperature is pretty warm, about 23C-27C (and many times the room temperature is even warmer)
I always have one or two 1.5L bottles of cold water in the fridge to use for the hot/cold mix.
When I mix water for the development I always mix 2L of 19C water in a large container.
for mixing the chemistry, I use about 1L of water, that leaves me with 1L of 19C water in the container.
During the development process, between agitations, I simply dunk the tank in the container with the remaining water.
I find this method much easier than using ice cubes, icy gels or other methods.