PC-TEA variants?

[Lachlan Young]

I have gathered together all the required ingredients to make 100ml of PC-TEA but I have two questions. There appear to be two different formulae for PC-TEA - one with 10g Ascorbic Acid the other with 9g - which is correct?
Secondly, what would be suitable starting times when diluted 1+50?

All help much appreciated,

Lachlan

 

[Jordan]

I have gathered together all the required ingredients to make 100ml of PC-TEA but I have two questions. There appear to be two different formulae for PC-TEA - one with 10g Ascorbic Acid the other with 9g - which is correct?
Secondly, what would be suitable starting times when diluted 1+50?

All help much appreciated,

Lachlan

I don't think either is necessarily "correct". I believe 10 g ascorbic acid was the earlier version, identical to the older PC-Glycol formula. The pH of this working solution will be lower (i.e. longer developing times -- but the difference may be slight) than one made with 9 g ascorbic acid.

I use the 10g version. For 400-speed films at box speed, about 8-9 min at 22C seems to be a good starting point.