Lith developer additives

[Tom Kershaw]

Assuming the use of Fotospeed LD20 or perhaps a public formula, I have been attempting to devise a set of additives for lith printing:

- Potassium Bromide solution for altering tone colour

- Benzotriazole for cooler tones (haven't tried this yet)

- Ammonium Carbonate solution to increase image contrast and colour etc. - I tried this after reading about Moersch Omega additive. However a 10% solution diluted 10ml solution + 990ml water for a working solution didn't seem to give much change in image tone with Fomatone 532 II; but as lith printing can be rather unpredictable I'm not sure how to assess any potential change caused by the Ammonium Carbonate solution.​

Any comments?

Tom

 

[Mark Fisher]

I've been thinking something along the same lines.....I just haven't had the time. I am particularly interested in how benzotriole and ammonium carbonate could alter the tone. I'm anxious to hear how your experiments go. I may give it a go with Slavich if I can manage to scrape up some time.

 

[Tom Kershaw]

The recommended dilution for the Moersch Omega additive is 1+100; perhaps the solution contains a greater concentration of Ammonium Carbonate.

Tom

 

[psvensson]

Lith developers already contain bromide or a similar retardant, so adding that will not alter image tone, just slow development.

I've tried benzo in my homemade lith developers. It does not alter image tone appreciably. Lith developers produce warm tones in part because development times are long, and the grains grow slowly. A lith developer with benzo will still develop slowly. If you want cold tones, try toning with gold.

I haven't tried ammonium carbonate.

 

[Tom Kershaw]

I've tried benzo in my homemade lith developers. It does not alter image tone appreciably. Lith developers produce warm tones in part because development times are long, and the grains grow slowly. A lith developer with benzo will still develop slowly. If you want cold tones, try toning with gold.

I was surprised as well at the suggestion of Benzotriazole in a lith developer, mentioned by Tim Rudman in his book. Toning lith prints in gold toner has resulted in attractive blue tones with Fomatone emulsions.

Tom

 

[psvensson]

I should mention that gold toner hasn't worked for me on RC lith prints - they turn a not very pleasing shade of purple instead of going blue.

 

[Rich Ullsmith]

In a fresh pan of developer (3 liters), I use 100ml of 1% benzotriazole. I can't tell you subjectively what difference it makes, but it seems like it gets a fresh pan of developer to behave more like a seasoned developer (longer times and infectious development). I don't add more benzotriazole when I replenish.