Quote Originally Posted by john_s View Post
I wonder if that reported effect was due to Dimezone-S or whether it would have occurred with phenidone also.
Alan and John: That's an interesting question. XTOL does fine, and it uses Dimezone-S. But its pH is 8.20. The pH of DS-10 is 8.00, which those slow films might not have appreciated. Based on your postings, I'll start with slow films when I do roll-tests again. The concentrate I'm experimenting with below has a pH of 8.08:

Propylene Glycol ..................... 12.2 g (grams, not ml)
Sodium Metaborate 4 mol ...... 1.8 g
Ascorbic Acid .......................... 4.2 g
Dimezone-S ............................ 0.09 g

A litre of developer contains 18 g of concentrate and 45 g of sodium sulfite with pH = 8.08.

Ill call this 212D. 212 is the mixing-date and the D means Dimezone. The amount Dimezone-S will change a little to adjust dev-times to be close to D316. My first test-strip (Tri-X) had higher than expected density. There's always a surprise in this business. The SM/AA ratio is 0.429, the same as Trial-130119, so its the same concentrate with less Dimezone; you simply use more of it. The composition of this is similar to D316 and its pH is the same, so the testing and times for D316 should also apply to 212D.

Mark Overton