Friday, June 4, 2010

More concentrated stock solution?

To make a more concentrated stock solution of GSD-10 would require only substituting potassium carbonate for sodium carbonate, and reducing the ratio of sodium sulfite to glycin to around 1:1. The more concentrated version would look something like:

Distilled water: 50ml
Sodium sulfite: 12g
Glycin: 10g
Potassium carbonate: 75g
Distilled water to 100ml

This concentrate would be diluted 1:50 for intermittent or rotary processing, and 1:100-1:200 for stand development.

I would expect to see an increase in the appearance of both grain and sharpness. Personally, I like the way GSD-10 balances of grain and sharpness, and so I would consider this concentrated version a compromise, especially for 35mm work.

Another option would be to double the concentration of GSD-10 by retaining the formula as-is, and simply making it up in 1/2 the water. This version would be:

Distilled water: 500ml
Sodium sulfite 100g
Glycin: 20g
Sodium carbonate: 150g
Distilled water to 1 liter

Dilute 1:10 for intermittent or rotary processing, and 1:20-1:40 for stand development.

I like this option better, since it would still be the developer I know and love, but I will try both options and compare them before coming to any conclusions. If anyone decides to experiment with these, or any other variations, I'd love to know about it. Please contact me at:

with any comments, questions or suggestions, and I'm always very happy to see images made with my developers.