Time/Temp Charts

[hortense]

Do all panchormatic films and/or their recommended developers respond the same to temperture regardinig development time?

 

[glbeas]

No, it depends on what developing agents are in the developer. Some kinds go dead quicker as the temperature drops, some have a more flat line response. They are similar enough to get you in the ballpark though using something like the development dial in the old Kodak Darkroom Dataguide if you don't use the developers at the extreme ends of thier ranges. Always do some testing before getting into serious work.

 

[David Brown]

... to get you in the ballpark though using something like the development dial in the old Kodak Darkroom Dataguide if you don't use the developers at the extreme ends of thier ranges. ...

I still have that "dial". Think I'm safe using it with ID-11 and Ilford's standard films (PanF, HP5, FP4)?

 

[fschifano]

I still have that "dial". Think I'm safe using it with ID-11 and Ilford's standard films (PanF, HP5, FP4)?

Yes.

 

[drpsilver]

18 April 2006

I have been using the "Kodak dial" for many years with good results. Just stay close to a normal developing temperature, i.e. 65F to 74F.

Regards,
Darwin

 

[Gerald Koch]

No, it depends on the developing agent(s) and they vary widely. Each agent has its own slope for the time/temperature curve. The commonly seen dial calculators are designed for MQ developers, but even here each mixture has its own slope depending on the M/Q ratio. Fortunately there is a lot of slop in the photographic process.

The equation is T2 = T1 * exp -k x (t2 - t1) where T1 and T2 are the times and t1 and t2 are the respective temperatures in degrees centigrade. For most common Kodak film developers a value of k = 0.081 can be used, closest for HC-110 and Xtol.