Compensating for very warm solution temp in film development?

[David R Munson]

It's summer here in Taiwan, and my "cold" tap water ranges from about 82-88º Fahrenheit on a normal day. Water, stored in bottles and let sit in the dark in an interior room, stabilizes at about 84º F. I'm used to making adjustments to development time based on changes in temperature, but not to this scale. In theory, I could turn on the AC in one of the rooms in my apartment and let everything stabilize in temp lower on the scale, but I'd rather not deal with the effect this would have on my electric bill.

Let's assume my standardized solution temperature is 84º F, and my starting time at 68º F for Tri-X Pan 320 in HC-110 Dilution G is 19.5 minutes. To compensate, I generally use a formula found on the Covington Innoivations HC-110 page, which is meant for a smaller range of compensation for temperature (recommended no higher than 75ºF). If I use the formula anyway...

New time = Old time × e^(-0.045 × (New temp °F - Old temp °F))

9.49 = 19.5 • e^(-0.045(84-68))

9.5 minutes doesn't seem unreasonable at face value, and I intend to give it a try tonight after work, but before I do I'm hoping someone with some knowledge on the subject might be able to tell my what problems I might run into when compensating for a solution temperature this high.

Any thoughts? Thanks in advance.

[baronvonaaron]

i'm on tour with a circus and i process in my trailer. the temp right out of mybottles is around 88F or so. i've just been putting the amount. that i need in the freezer for about 10 minutes and i cools it down to round 68F.

dunno if thst's a no no. but everything is developing just fine for me.

[venchka]

I had a math teacher once who said, "You don't need to remember everything, you just need to remember where to find the answers."
Here is a table published by Ilford. It stops 27C/80F. You can use it to verify/tweak your math.

http://www.ilfordphoto.com/Webfiles/2006210208211880.pdf

I fight the same problem, to a lesser degree, in the summer here in Houston, TX. I tried putting my chemicals in 1-2 liter bottles in a sink full of water and adding blue ice until I got down to 68F. With ambient temperature at 78F-79F, the 68F water would rise to 72F-73F in 3-4 minutes in my Jobo drum. I tried 65F with similar results. I then discovered that the same sink full of chemicals would stabilize at 75F-76F in a few hours. I now use the Ilford time conversion for 24C/75F and everything is fine.

Good luck!

[Brian Ellis]

If you can find one on ebay or somewhere else, a Zone VI Compensating Developing Timer is an easy way to deal with the problem of fluctuating temperature changes in the developer solution. I used one for many years in my Florida darkroom, where temperatures could range from about 85 degrees at the start of a session to 65 degrees when the AC took full effect.

[David R Munson]

I've already gone from Dilution B to Dilution G (from 1:7 stock:water to 1:31), which gives me room to contract development time because of temp. I'm also limited by the fact that HC-110 and D76 are basically the only two developers I can get here.

I'll be doing a test batch of four sheets tomorrow night. I'll follow up here with my findings. :)

[Leigh]

You might consider Diafine. It's an excellent compensating fine-grain developer.

It's rated for use from 70°F to 85°F with no change in times, and will probably work OK at higher temps.

- Leigh

[Jim Noel]

Either cool the diluting water, or get some ice.
FInd out how much the temperature increases in the length of time it takes to develop by putting water in the container at about 65-68 deg F. Agitate as if film were present. At then end of the time, check the temperature.
Let's say the temperature rose 12 deg F. CHeck the chart for a developing temperature 6 deg. higher than the starting temp.
This is a system used for years by those of us who developed our own color in the days when home chemistry first became available. It is a "drift by" system.

[BetterSense]

I also enjoy using Diafine with roll films during the summer when the solution might be 27C or more. It's an excellent developer within a narrow window of uses.

[Michael E]

The ice cube/fridge method has one drawback: The final rinse will be at tab water temperature. Changing the temperature too fast is not good and can result in excessive or even wrinkled grain.

Michael

[David R Munson]

I'll post a photo when I can, but I just did my first batch of sheet film in 4+ years, compensated using the formula above, and the negatives look great.

[David R Munson]

w00t

http://farm7.static.flickr.com/6002/5933917190_aba1d88895_z.jpg (http://www.flickr.com/photos/davidrmunson/5933917190/)
Insignificant Photo (http://www.flickr.com/photos/davidrmunson/5933917190/) by David R Munson (http://www.flickr.com/people/davidrmunson/), on Flickr

[venchka]

Either cool the diluting water, or get some ice.
FInd out how much the temperature increases in the length of time it takes to develop by putting water in the container at about 65-68 deg F. Agitate as if film were present. At then end of the time, check the temperature.
Let's say the temperature rose 12 deg F. CHeck the chart for a developing temperature 6 deg. higher than the starting temp.
This is a system used for years by those of us who developed our own color in the days when home chemistry first became available. It is a "drift by" system.

As I noted earlier, I tried this approach. I measured the liquid at 1 minute intervals. The temperature rose about 80% of the total in the first 30% of a 10 minute developing cycle. In other words, the temp. rose from 65F to 73F in the first 3 minutes and stabilized at 75F about 6-8 minutes in. The temp. rise was not linear. That is why I switched to 75F for all of my liguids.


The ice cube/fridge method has one drawback: The final rinse will be at tab water temperature. Changing the temperature too fast is not good and can result in excessive or even wrinkled grain.

Michael

I use Jobo's idea of 10 wash cycles of 1 minute each. I can process a Jobo 3010 full of film from pre-wash to final wash rinse with less than 10 liters of water. All of those containers of water plus fix go in my sink full of water stabilized at room temperature. I place the distilled water & Photo-Flo in my final rinse bucket in the bathroom where I hanf film. All of my liquids are within plus or minus 1 degree of each other. My results are consistant.

Ilford's 3 wash cycles with increasing inversions would work for small tanks.

[Greg Lockrey]

I didn't have time to read all of the answers so I may be repeating here. Put some ice in baggies as not to dilute the chemicals with melted water and remove if the temps get too low and replace if they start to rise. Whatever is happening in the developer will be close enough for rinse and fix.

[clair mcknight]

i keep an opened (3/4's full with water) aluminum soda can in my freezer and another in the darkroom for hot water. if you swirl the can around for a minute or two (with a thermometer), you can cool down or warm up a chemistry in just a few minutes. good luck!

[nickademusss]

I too have had some warm days in the darkroom, I have used with great success, the gel packs you use in your cooler.

I simply set the trays on them, for the 5x7 trays one is enough, two for the larger trays, they are cheap and easy to use.

Tap water here is 76 deg, the gel packs are below freezing so it takes a vigilant eye to make sure the soup doesn't get to cold.