Photographer's Formulary still sells Potassium Dichromate: https://stores.photoformulary.com/potassium-dichromate-class-6-1-bichromate-ground-ups-only-dea-form-required-choose-ups-ground-shipping-at-checkout/
For sulfuric acid I've successfully used battery acid from an auto parts store, for example the SDS sheet for this stuff says it contains 30-43% sulfuric acid (diluted in water): https://www.oreillyauto.com/detail/c/super-start/battery---accessories/battery-accessories--universal-/battery-chemicals/8d0625b693a9/super-start-1-quart-battery-acid/sbe3/cycleacid?pos=0 <https://www.oreillyauto.com/detail/c/super-start/battery---accessories/battery-accessories--universal-/battery-chemicals/8d0625b693a9/super-start-1-quart-battery-acid/sbe3/cycleacid?pos=0> This Dichromate (not Permanganate) R-9 recipe is adapted from Tish Stringer's excellent B&W Reversal Processing Guide </>, and is identical to the one in Kathryn Ramey's *Break The Machine* To Make: 1 L 2 L 4 L Water, 20°C (68°F) 975 mL 1950 mL 3900 mL Potassium Dichromate 9.5 g 19 g 38 g Sulfuric Acid 48% solution 25 mL 50 mL 100 mL (Always make the recipe in the sequence written, adding the smaller volume of concentrated sulfuric acid to larger volume of water) When handling/measuring Potassium Dichromate use protective equipment to prevent skin contact or inhalation and take care to prevent powder from becoming airborn/use a respirator On Thu, May 21, 2026 at 1:05 AM Ed Inman <[email protected]> wrote: > Battery acid from an auto parts store is roughly 1/3 sulfuric. Dichromate > or Permanganate can be found on ebay. > > If you have any training as a chemist you can pretty easily look up the > formulas and do the math. > > Just be aware you are dealing with potentially very hazardous materials. > > > > > -- > Frameworks mailing list > [email protected] > https://mail.film-gallery.org/mailman/listinfo/frameworks_film-gallery.org >
-- Frameworks mailing list [email protected] https://mail.film-gallery.org/mailman/listinfo/frameworks_film-gallery.org
