Fine Grain Developer - 1940 "The Camera" Lucerne.

[Ian Grant]

THE BRITISH JOURNAL PHOTOGRAPHIC ALMANAC, 1941. 148/9


An Inexpensive Fine-grain Developer. The following is an inexpensive fine-grain developer which is stated never the- less to give very excellent results.


Metol. . . . . . . . . . . . . . . . . . . . . . . . . . 37 gms.
Sodium sulphite (anhydrous). . . . . . . . . . . 136 gms.
Kodalk / Sodium Metaborate . . . . . . . . . . .57 gms.
Potassium bromide . . . . . . . . . . . . . . . . . 12½ gms.
Water to . . . . . . . . . . . . . . . . . . . . . . . 1,000 c.c.


For use, this stock solution should be diluted with eight volumes of water. Development times for super speed pan- chromatic material are of the order of 30 min. at 65° F., or 22 min. and 18 min., respectively, for fast and for extra fine grain material. The developer may be thrown away after use, but the stock solution will keep well if properly stoppered.

“The Camera,” Lucerne, May, 1940, p. 327. B. J ., 1940, Sept. 13, p. 451

[Mike Wilde]

interesting. Kind of like D-23, with a bit more alkalinity, and quite a fair chunk more of restrianer. I only ever recall that much bromide per litre with strong lith film developers (it might have been called D-85?) of a much higher pH

[Ian Grant]

Mike, it has to be remembered that this is a concentrate so the Bromide's not that high when dilute and the Sulphite level is approx 15% that of D23/DK20/Microdol/D76 etc.

The working solution is:

Metol. . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 gms.
Sodium sulphite (anhydrous). . . . . . . . . . . 15.1 gms.
Kodalk / Sodium Metaborate . . . . . . . . . . . 6.33 gms.
Potassium bromide . . . . . . . . . . . . . . . . . 1.38 gms.
Water . . . . . . . . . . . . . . . . . . . . . . . . . 1 litre

That then makes more sense.

Ian

[Mike Wilde]

Sorry, Ian, missed the concentrate bit in my initial early morning scan of the text, and obviously too hasty a reply.

[Michael R 1974]

I'm confused. With a higher pH/stronger accelerator than D23, making this a more active developer, and a relatively low sulfite level, how would this be a fine grain developer?

[Ian Grant]

Well the amount of Sulphite is relatively high in comparison to Beutler's High Definition developer, 15 g/litre as opposed to 5 g/litre in the working solutions D23 or D76 at 1+3 would be 25 g/litre

If we take Beutler as the one extreme - Metol with a low sulphite level and the D76/D23 high Sulphite level as the other then this developer fits somewhere in the middle. The relationship between sulphite level and fine grain isn't prportional.

This was probably a fine grain developer of it's time relative to older developer formula. It has to be remembered that until 35mm film usage became wide spread most film developers were like D72 or Pyro based and people developed to very much higher gammas and densities.

Kodak Research only published their first Fine grain developer in 1927 followed by D76 as a cine developer (not recommended at that point for still cameras). This developer was published in 1940, D23/D25 were only published in 19444.

These days D76/ID-11 which was in effect an Open Sorce formula is taken as the benchmark to compare other Fine grain developers against, by the 1940's and 50's nearly every manufacturer made it - Defender 6, Foma FV3, Forte FD20, Foton N12, M&B 320 are just some of the names it was sold under. It became a standard because the Movie industry needed standardised processing regardless of where films were processed around the world.

I wouldn't give this particular formula to much importance as it is but by switching to Potassium Sulphite (because of it's higher solubility) and increasing the Sulphite level you would get you closer to some commercial one shot concentated developers.

Ian

[Michael R 1974]

Makes sense. Thanks for the clarification.

[Trask]

Same weight Potassium Sulphite as for Sodium Sulphite, do you think?

[Ian Grant]

You'd need to use slightly more as it has a higher MW, so x1.25.

Ian

[albada]

PhotoFormulary.com sells a 45% aqueous concentrate of Potassium sulfite. My calculations say that 10 grams of Sodium sulfite corresponds to 27.9 ml of this 45% Potassium sulfite.

Mark Overton