Divided D23 by Ed Buffaloe
Recently someone on the Large Format Forum was trying to find an article (by Jim Veenstra) from an early issue of View Camera magazine on the Divided D23 developer. I happened to have the article, so I shared the formula and developing information with him. While I was at it I read the article again myself. It piqued my latent interest in divided developers, so I read up on them a bit more and did some minor experimentation. This brief article is designed to provide the basic formulas, point out the obvious relationships between them, and provide links to various resources for further information both on and off the web.
My first thought when seeing the Divided D23 formula was that it’s not really a divided formula at all (it’s D23 with an alkaline afterbath). This led me to compare D23 with
D25 and D76, and the relationships were immediately apparent.










750 ml

750 ml

750 ml

750 ml

750 ml


7.5 g

7.5 g

2 g

7.5 g

2 g


100 g

100 g

100 g

100 g

100 g




15 g












5 g



5 g






2 g






1 liter

1 liter

1 liter

1 liter

1 liter














2 g

2 g








1 liter

1 liter


D23 has 7.5 grams of metol and 100 grams of sodium sulfite. That’s it. D25 simply adds 15
grams of sodium bisulfite. D76 reduces the metol to 2 grams, then adds 5 grams of hydroquinone and 2 grams of borax. Solution B for the divided developers is simply 2 grams of borax in a liter
of water.
There is a variant of the Divided D23 formula by H. Stoeckler, in which he reduces the metol to 5 grams in solution A and increases the borax to 10 grams in solution B. Anchell’s The Darkroom
Cookbook gives another variation of the Stoeckler formula, in which solution A has the sulfite reduced to 80 grams and 20 grams of sodium bisulfite is added; he also gives a Divided D23
Variant wherein the metol is reduced to 5 grams (a la Stoeckler) and the borax in the second bath is increased to 18 grams in only 500 ml of water. Joseph Lipka uses a variant that substitutes
sodium metaborate (Kodalk) for the borax in solution B.






750 ml

750 ml

750 ml

750 ml


7.5 g

5 g

5 g

5 g


100 g

100 g

100 g

80 g








20 g


1 liter

1 liter

1 liter

1 liter







2 g

18 g

10 g

10 g


1 liter

500 ml

1 liter

1 liter


Supposedly a divided developer has the developing agent in solution A and the accelerator in
solution B. But obviously any solution A with 100 grams of sulfite in it has enough alkalinity that
it can function as a developer without the addition of further accelerator. So when films are in the
above solution A’s, they aren’t just absorbing developing agent and waiting for solution B to provide enough alkalinity to begin developmentthey are developing the film. But solution B is
where the compensation comes in. In solution B the developing agent quickly exhausts itself in the high values where the greatest density lies, while the low values continue to develop. So,
essentially, you develop in solution A until your high values are almost where you want them, then you place the film in solution B and develop until the shadow values are where you want them. If
you are not experienced at development by inspection, you may have to do a little experimenting to
get the times just right.
Presoaking in water is not necessary. Use your normal agitation method in solution A, and unless
you want a very strong N2 contraction, go ahead and give 1015 seconds of agitation per minute
(or more) in solution B as well. (For N2, don’t agitate solution B at all.) Increasing the time in
solution A raises overall density and contrast, whereas increasing the time in solution B will only raise shadow detail if the film is returned briefly to solution A first.
Jim Veenstra gives some suggested developing times in his article, and since the article is so hard
to come by I am going to reproduce his suggestions here. You will note he considers that D23 does not require the second bath with TMax films except for an N2 contraction.






















200

4m

3m

4.66m

3m

5m

4m

7m

4m

9.5m

4m

15m

4m


100

5m

4m

6m


7m


9m


13m


20m



400

4m

3m

5m


6m


7.5m


11m


16m



Just to test the above times, I developed two 4x5 pinhole negatives in the standard Divided D23 formula. The film was TMax
400, rated at 320, developed for 7 minutes in solution A and 2 minutes in solution B at 68°F. The results compared quite
favorably to my PMK negatives of the same subjects. I plan to use this developer in the future for N1 and N2 contractions.
References:
Ansel Adams. The Negative. Boston: Little, Brown & Co., 1981.
Pp. 229232. Stephen Anchell. The Darkroom Cookbook (2nd Edition). Boston: Focal Press, 2000. Pp. 143147. Jacobson & Jacobson. Developing (18th Edn., Rev.). London: Focal Press, 1978. P.237. James M. Kates. The Stoeckler TwoBath Film Developer. http://www.cs.berkeley.edu/~qtluong/photography/lf/twobath/ Kodak. Chemicals & Formulas for Black and White Photography (7th Edition). 1973. Jim Veenstra. “Divided D23 as a Film Developer,” View Camera, Vol. 2, No. 5, Sept. 1989. Pp. 1216.



