Cadmium Free vs Lea Formula #1
Jun 28th 2019
A lot of my focus has been on Cadmium free Collodion's, so I wanted to show, as best I can, the difference (or same-ness) of a couple of different formulas. I’ve done many multiple plates using these formulas, so I’ve tried to choose representative samples of each. They are all from my standard shot, using the same silver bath, developer, fixer and varnish. The only variation is exposure time for the UVP #3 All Lithium formula.
Collodions shown:
Lea Formula #1 – this is a classic Ammonium Iodide, Cadmium Bromide Formula that is similar to Quinn’s Quick Clear.
UVP Formula #1 – this is an Ammonium Iodide, Lithium Bromide Formula that behaves similarly to the Lea#1
UVP Formula #3 – this is a Lithium Iodide, Lithium Bromide Formula that is 1 or more stops faster that the other two standard speed formulas.
The Lea 1 and UVP 1 were both exposed for 7 seconds while the UVP 3 was between 2 and 3 seconds.
They are all very close, but I prefer the UVP #1. The UVP #3 has less detail in the blacks, so opting for speed seems to give you a little less tonal range. I’m going to play with this formula to see if I can improve it while maintaining the speed.
Other things I am working on:
- Different developer formulas that I will share at some point.
- A new Cadmium Free Collodion that is faster than the UVP #1, but slower that the UVP #3. It seems to give great tone and contrast. The only drawback I see right now is that it is harder to visually develop. I might be looking for a few people to beta test it for me. Let me know if you might be interested.