How important is temperature in developing B&W film?

[vinyljunky]

Didn't find any threads on this topic, just curious to know how important temperature is in B&W developing? I always used water straight out of the faucet, but I recently measured the temperature and found it was 23 deg C/73.4 deg F (versus the recommended temperature of 20 deg C/68 deg F).

Does everyone measure the temperature for B&W developing? Has anyone noticed any issues with hotter/colder temperatures? Do any film/developer combinations need precise measurement?

 

[benlees]

It's pretty important to keep temperatures on your mind because the amount of time the film is in the developer depends on the temp! Keeping in mind exposure, desired contrast, neg. "thinness", and stuff like that.

 

[BillBingham2]

68, it's what my thumb is calibrated to.

Unless I push, then it's a bit hotter.

B2

 

[sreed2006]

The rate of chemical reactions varies with temperature. The higher the temperature, the faster the reaction. That's Chemistry 101.

Because of this, a specified development time is tied to a specific temperature. For consistent results, use the specified time at the specified temperature.

 

[Keith]

I'm very particular with temperature ... why create a variable you're unsure of when tailoring your process.

 

[Rayt]

The water gets pretty warm here in HK so I use ice to lower the developer to 68F. usually the development time is under 10 minutes so the risk of the temp rising in the tank is minimal. If you use a warmer temperature then you need to compensate with shorter development time. There is a chart you can find online but I find that to be a crude estimate. I tend to stick to 68F for consistency.

 

[Mackinaw]

The temperature of the developer is very important if you want good negs. Almost all of the film manufacturers suggest using 20 degrees C, or 68 degrees F as your baseline. If that isn't possible where you live, you'll need to compensate, either up or down, from 20C/68F. Ilford has a nifty temperature compensation chart on their website that you can download and use to help determine first developer times. I use this a lot.

Jim B.

 

[raytoei@gmail.com]

i used to be paranoid about temp until i started developing at 30C, which i roughly halved the development time for 20C. This produces large grains with certain emulsions. I checked my recent photos developed this way, and it affects neopan 400 most. your mileage will definitely vary as the development process affects it too.

for me, rodinal stand (40mins) + neopan 400 at 30c = Large grains which is not as nice as small sharp grains i get with 20C.

See Nobuyoshi Araki video, http://vimeo.com/22064514
he has some examples where his film was developed at very high temperature, the photos looks very apocalyptic.

Developing film at uneven temp may result in retriculation, giving clumpy grains that looks like small dots.

raytoei

 

[Oren Grad]

You can develop B&W film with excellent quality at a range of temperatures - anywhere between 68F and 75F is common, and sometimes it's necessary to work outside even that range. But because the rate of chemical reactions depends on the temperature, for consistent results you need to adjust the development time to match the temperature. Kodak, Ilford and Fuji all provide time/temp tables or charts for their films to help you make that adjustment.

Some B&W film/developer combinations, for example Tri-X or HP5 Plus in D-76 or ID-11, have so much latitude in processing that you can be off quite a bit on time/temperature and still often get printable negatives. But it's not hard to adjust for temperature, so why make your life more difficult when it comes time to print?

 

[maddoc]

I monitor the temperature and keep the tank between inversions in a big beaker containing the water later used for rinsing. Also I avoid rinsing film with tap water since it is more effort to keep tap water at constant temperature than to wash film following the Ilford method (also helps saving water). If temperature is not 20C (for example for me in summer it is impossible to go below 23C) then I compensate according to the Iphone application I generally use for developing BW films (Massive Dev)

 

[John Bragg]

I think the only time I would guess is if I had a tragic accident with my thermometer. 20c all the way.

 

[Bingley]

Depends on the developer. It's pretty important w/ some developers, like Rodinal. With others, like Diafine, not so much.

 

[rizraz]

I do measure, but I take the average of the start and finish..... it is usually roughly around 18-22 Celcius...... so you get a 20C average 🙂

Might not be the best idea, but it works for me.

 

[SausalitoDog]

Consistent temps is the only way to have consistent results...or to be able to predictably alter the outcome.

Best way is a thermometer in the faucet (generally with a hose type connection)

 

[kknox]

Freestyle has a chart for temps and times.

 

[Godfrey]

Temperature consistency is the most important aspect, as well as keeping within the boundaries that a particular set of chemicals was designed to work at.

 

[Chris101]

The rate of chemical reactions varies with temperature. The higher the temperature, the faster the reaction. That's Chemistry 101.
...

102. We don't get into temperature dependent rate law until second semester cause you really need to have differential calculus as a prereq.

 

[Gabriel M.A.]

Development is chemistry. Temperature is inherently important.

 

[maddoc]

102. We don't get into temperature dependent rate law until second semester cause you really need to have differential calculus as a prereq.

The good old Arrhenius law me thinks ... k = A*exp(-Ea/R*t) ... 😀

 

[Chriscrawfordphoto]

It is very important if you want optimum quality. You do not always have to process at 68 degrees, but you do have to adjust the developing time for the temp you do use. I often process at 75 degrees in the summer because our tap water is around that temperature in summer where I live, and you need the wash water to be the same temp as your developer and fixer. I have tested developing times at different temps for that reason.