Ansco 130 & KBr

[Alan9940]

After a long absence from using this developer formula, I decided to pull the Glycin out of the freezer and mix a batch. The "standard" formula I have calls for 5.5g of KBr, while the Ansel Adams version says to add KBr, as needed, to prevent fog; which sounds like AA didn't normally use it. Curious what all you Ansco 130 users do with the KBr? Since most of the paper formulas that I typically use call for around 2g of KBr, that's the amount I added this morning to make 1L.

 

[Milpool]

Interesting question.

Modern papers of the non-rapid variety (generally speaking) are very likely less fog-prone than they once were. For example (anecdotally) when I used to use Polymax FA and MGIV I found I got no fog with 1g/l KBr in D-72.

With Ansco 130 and your chosen paper I suppose you’d have to test for chemical fog with 2g/l KBr and adjust from there.

Adams used several variations, some without HQ etc. Since the old rule of thumb was that more KBr leads to warmer tones he probably wanted to use the minimum required to prevent fog.

My guess is with most current/neutral papers, which are relatively resistant to developer modifications, the difference between 2g/l (assuming no fog) and 5.5g/l KBr will be negligible, but you never know for sure until you try something.

 

[DREW WILEY]

KBr is the standard restrainer in Ansco 130. Benzotriazole is a possible substitute, used at 1/10th the gram weight as KBr, but affects the image color differently. I can't imagine leaving a restrainer out - you wouldn't get clean highlights. I doubt AA was implying that - even his published personal tweaks of 130 included KBr. He sometimes upped the hydroquinone; but then you start losing some of the special quality of 130, and things start looking Dektol-ish instead.

I happen to mainly use gold chloride toner to cool images, and that actually responds better when standard KBr is the restrainer in play, rather than Benz.

I generally use 4g KBr per liter of 130. If it is benz instead, just 0.4 g instead. You can also partially combine them if you wish, experimentally.

 

[Alan9940]

Thank you both for the input.

I thought about using 4 - 5.5g of KBr because I like warmer prints, in general. But, I remember from prior testing that the "color" difference between, say, 2g vs 4 or 5g KBr wasn't all that apparent with today's neutral to cold tone papers. That said, it was a long time ago when I was playing around with these formulas so my memory may not be so good! I'll start with the 2g KBr that I already tossed in there and see how it goes with Ilford Classic; I can always add a dash more, if needed.