B&W Reversal Processing Notes

Rather than being a real article, this page is more of a collection of notes (primarily for my own use) on black-and-white reversal processing formulas. Over the years I’ve been interested in making B&W slides at home, with the goal of making the process as simple and inexpensive as possible. One of my major aims was to come up with a set of formulas based as much as possible on commercial developers and other solutions. With that in mind, here are some reversal formulas that I have tested.

Note: These recipes are intended for use by those who are already familiar with black-and-white reversal processing. I am not responsible for ruined film or equipment, poor results, or any damage to your health that may result from your use of these formulas.

First incarnation: B&W reversal based on an HC-110 first developer

HC-110 is a versatile developer that can be used for all kinds of purposes (along with standard negative development). Here I’ve boosted it with sodium carbonate to make an active first developer for reversal processing.

First developer

6 tsp Na2CO3
15 ml HC-110 syrup
(2 g KBr – optional)
8 g sodium thiosulfate
Make up to 500 ml with water.

This developer should be mixed fresh before each use.


Part A: 4 g KMnO4 in 1 L distilled water
Part B: 55 g NaHSO4 (this is sodium bisulfate, not bisulfite!) in 1 L distilled water

Mix equal volumes of A and B immediately before use. It keeps for a few hours at most.

Clearing bath

30 g sodium metabisulfite in 1 L water

Fogging re-developer

2 g thiourea (thiourea is also known as thiocarbamide)
100 g Na2CO3
Make up to 1 L with water.

An alternative to this fogging re-developer is to use the “B” (toner) part of an odourless sepia toner kit.

Directions: The first developer gives EI 64 with Ilford Pan F Plus developed for 8.5 min at 24C. Bleaching should be carried out for about 5 minutes, clearing for about 2 minutes, and redevelopment for another 2 minutes, though the latter two steps are probably finished much faster than this. Use standard washes between each step.

Drawbacks: This method gives nice chocolate-coloured slides (you can use a traditional light reversal if you want neutral blacks) but the permanganate bleach damages the emulsion. Might be good to run the process at a cooler temperature or use some kind of hardening stop bath.

Second incarnation: B&W reversal based on Ilford’s procedure

The “Reversal processing black-and-white film” PDF on the Ilford website describes a reversal method using developers based on Ilford PQ Universal or Ilford Bromophen (both paper developers). I modified their recipes and procedures slightly for best results.

First developer

Ilford’s version: Ilford PQ Universal diluted 1+5 with water containing 12 g/L sodium thiosulfate (for FP4 Plus).
My version: Use 8 g/L sodium thiosulfate instead.


Ilford recommends a standard permanganate bleach.
My version: sodium bisulfate (65 g/L) and potassium dichromate (10 g/L) in distilled water.

Clearing bath

The use of a dichromate bleach requires a sodium sulfite clearing bath — I use 5% aqueous sodium sulfite.

Fogging re-developer

Same as the “first incarnation”.

Directions: I follow the Ilford directions on this one but give FP4 Plus 9 mins at 20C in the first developer (Ilford recommends 12 mins). My preliminary experiments seem to indicate that this gives an EI of about 100 give or take half a stop. The dichromate bleach makes the emulsion much more resilient but this may make it harder to do the final wash.