Kodak DK-50 Film Developer

Medium grain developer with a tendency to produce an upswept density curve.


Mix chemicals in the listed order. Make sure each chemical is completely dissolved before mixing the next one. Mix a pinch of the sodium sulfite before mixing the metol. Use distilled or deionized water for improved keeping properties. The stock solution may be diluted with tap water at the time of development.


Chemical Amount
Water (50 °C) 500 ml
Metol 2.5 g
Sodium sulfite (anhydrous) 30 g
Hydroquinone 2.5 g
Sodium metaborate (Kodalk) 10 g
Potassium bromide 0.5 g
Water to make 1000 ml

Replenisher DK-50R

Chemical Amount
Water (50 °C) 750 ml
Metol 5 g
Sodium sulfite (anhydrous) 30 g
Hydroquinone 10 g
Sodium metaborate (Kodalk) 40 g
Water to make 1000 ml


Use undiluted or diluted 1+1. For use with DK-50 diluted 1+1, also use replenisher diluted 1+1. Replenish 30 ml per roll or more if negative density is not maintained.

Starting development time is 5 to 6 minutes diluted 1+1 at 20°C.


The following is entirely anecdotal.

DK-50 tends to produce high contrast negatives, especially when used undiluted. The developer mellows after replenishment. Grain is not the finest and use with 35 mm negatives may best be avoided (but so is Rodinal). The density curve is upswept (similar to HC-110). Back in the day it was commonly used as a portrait developer with controlled lighting.

Date: 2022-11-28