Cadmium Free Collodion – Lithium Bromide / Lithium Iodide Collodion

Initial Results.

I mixed up some collodion using lithium bromide and lithium iodide.  Both salts are soluble in ether/ethanol, so it was a pretty straight forward process.  I added both salts to the ether and ethanol, mixed until dissolved, then added the collodion USP.  It was a pale yellow color, similar to the cadmium version.  Since there is no Potassium in the formula, there is no potassium bromide precipitate to worry about.  I aged it for one day then shot a plate.

Ripened 1 day

At one day it already behaves different than the cadmium version.  Using my standard setup and exposure time, I was able to get an image, but it was flat and foggy.  The same shot with the cadmium version I was just getting a white plate at various exposures.  Unfortunately I didn’t vary my exposure times to see if a shorter time would have given a decent plate. I was testing a series of formulas, and I just thought it need more ripening.


Ripened 9 days

My first plate again was flat and foggy, but better than the first shot at one day.  This time I varied the time to see if I could get a plate with good tone, contrast and no fog.  Well, I did!  My typical exposure time using my standard shot is 6 to 8 seconds, maybe down to 5 for some formulas.  Well, the all lithium formula gave me an exposure time of 2 seconds.  Nice contrast and tones with no fog.  This might come in handy when doing in-studio portraits.  It may actually be too fast for some conditions using a fast lens.

Now I need to see how long this formula stays fast.  Will it degrade quickly?

To be continued…

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A wet plate collodion photographer trained in chemistry and interested in new ways to do an old process.

One thought on “Cadmium Free Collodion – Lithium Bromide / Lithium Iodide Collodion”

  1. Hi Sergei,

    Iodine tincture can be added to the Formula 1 if you are going to mix and use that day. On the Lea #3 I haven’t tried it. I think it might cause it to age faster, and the whole appeal of #3 is it’s stability for long periods of time.

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