30 tablets @ 500 mg generic acetaminophen (crushed -- I used an 8 ounce hammer with the tablets in a postal envelope)
50 g sodium sulfite
20 g sodium hydroxide
water to make 250 ml
Start with about 150 ml room temp water. Stir in the acetaminophen and sulfite (I used sodium sulfite stock solution I already had); solution will be nearly opaque and white. Don't worry about the little rags and tags of tableting material; they don't seem to affect anything. Add the sodium hydroxide, stir, seal, and let stand for at least 24 hours; activity may continue increasing (as the reaction converting acetaminophen to p-aminophenol proceeds) for up to 48 hours from mixing. If the solution isn't as dark as weak tea with milk, at a minimum, it needs to stand longer.
As solution ages, you may note a layer of less opaque, darker colored solution floating on the denser, chalky looking portion; stir this together before using. After about a week, clear needle-like crystals will precipitate; leave these in the solution and stir before drawing off concentrate for use. Color will continue to darken from tan, to pink, to brown; as with Rodinal, this does no harm.
Dilute like Rodinal, use Rodinal times, though use of the sodium salts instead of corresponding potassium compounds in formulation is said to result in "softer working" developer, so if you're already a Rodinal user you might find you need to adjust times slightly to keep the same contrast. Don't attempt to use 1:100 until the solution is at least pink.
This formula originally comes from a discussion thread on rec.photo.darkroom newsgroup about two years ago, BTW, though the poster then cited another worker whose work I haven't seen. I'm sold; if you buy the acetaminophen at Costco, use Red Devil brand lye, pay $5/lb for your sulfite, and buy distilled water at 97 cents a gallon, this developer costs about 55 cents for the above quantity, which will develop about 50 rolls at 1:50 (35 mm or 2x120 on a 220 reel). Use of distilled water for dilution will, of course, increase cost per roll for the working solution, but it's still around 25 cents a roll; I usually factor out the distilled water, since it's essentially a constant for a given amount of film. Fomapan 100 gives *excellent* results in this soup; TX and Classic 400 in 120 are pretty nice, too, though the grain might be objectionable in 35 mm. I've been using it at 1:50 with reduced agitation, adding 50% to published Rodinal 1:50 times to account for agitating every 3rd minute.
