HC110 - lowest temperature for correct working / fog prevention?

[James1]

I've had good success developing expired films at reasonably standard temperatures but would now like to try lowering the temperature to see if fog can be reduced or eliminated.

From Googling, HC110 is the developer that's recommended for old or expired films, but while there are plenty of references to reducing temperature in order to minimise fog, I haven't managed to find anything which states the lowest temperature at which the HC110 will work properly (without its hydroquinone losing activity).

There are a number of posts where development has been carried out using very concentrated HC110 at almost 0*C, but I don't believe this necessarily means that the HC110 is working as intended. Kodak themselves quote temperatures from 18*C.

Does anyone know the lowest temperature that HC110 can be used at while retaining the activity of both its developers? 16-17*C? Or lower?

Thanks for any help!

 

[Gerald C Koch]

Hydroquinone becomes inactive as a developing agent below 55F. It illustrates that developing agents vary in their reaction to temperature. Developing rates drop very low with reduced temperature. For low temperature development near freezing a special developer is required which contains either sodium hydroxide as an activator or Amidol as a developing agent.

Lowering the temperature of development will only work if the rate of development of fog centers becomes less than the overall rate of development. I'm not sure that this is the case or if the two rates are dissimilar enough. Perhaps PE can answer this question. Unless fog is uneven which is usually not the case with age fog you can print through the fog and get a usable image.

 

[James1]

Thanks Gerald. I was planning to try at about 15*C (with a corresponding increase in development time), so HC1110 should still be just about active.

I'd be using Dilution B, so the increased time won't be that long even if it doesn't actually reduce the amount of fog....

 

[Gerald C Koch]

I would first do a test to see what the correct time would be at this temperature. It might be quite long.

 

[James1]

Absolutely. Planning on +50% to start, then taking it from there...

 

[Denverdad]

As I mentioned in (there was a url link here which no longer exists), I have had success developing found film in HC-110(A) at temperatures as low as 40F (~4C).