Am I only one to mess up carbonate? : LUSENET : B&W Photo - Film & Processing : One Thread

As I described below, I used too much potassium carbonate in my FX-2. The formula calls for crystalline, but anhydrous is much more easily available. The conversion factor is *not* the same as for sodium carbonate. Anybody else get caught on this? It seems like an easy error, yet I've never seen the topic brought up on the several sites that discuss the FX-2 formula?

-- Conrad Hoffman (, February 03, 2002


In my PF kit, part b is 123g of Potassium Carbonate (anhydrous) in a liter of water.

Out of curousity- what sites discuss the FX-2 Formula?

-- Mike DeVoue (, February 04, 2002.

Interesting, as Anchell gives 75 grams of crystalline in a liter of water as part B. Crystalline has water, so you need less of the anhydrous. 0.4182X less to be exact. Unless I'm confused (happens often) that would be about 31.4 grams/liter. I got the numbers using the formula weights in Lang's Chemical Handbook. Makes me wonder if PF is using the Kodalk modification, as 1.5X of that is used. If somebody understands this better, I sure hope they speak up! Do a search in using FX-2 and developer as keywords. Use both words so you don't get non-photo FX-2 stuff. Several sites will turn up.

-- Conrad Hoffman (, February 04, 2002.

Hey, I'm wrong! See new question/topic!

-- Conrad Hoffman (, February 05, 2002.

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