Monday, May 13, 2013

I have a feeling...

When I decided to restart making traditional photography, the first think I did was to buy a 5 liter jerrycan of ammonium thiosulfate, the so called rapid fixer. I intended to use selfmade developers, but at the time I thought there was no way to overcome the use of the fixer of ammonium thiosulfate, other than the unfashionable hypo (sodium thiosulfate). When I was young, I have used hypo and I knew that the time to fix was about 10 minutes. Then the brands start offering rapid fixer (ammonium thiosulfate) and hypo was forgotten.

Now, for a while, when I was still using commercial developers like R09 and Ilfosol 3, I had no problems with the fixer. But since I am using coffee (and vit.C) based developers, I am getting some annoying white spots in the positives which corresponds to opaque deposits on negatives. I discovered that washing very well the negative after the development with caffenol, there were less spots but still some.

To be sure that the combination coffee&ammonium thiosulfate was to blame about the spots I decided to not rinse in between and I had pictures like this:

Coffee+Vit.C developer + Ammonium Thiosulfate fixer
At last, I decided to use the old hypo (sodium thiosulfate) instead of ammonium thiosulfate. The time makes no difference to me. First I had to prepare the sodium thiosulfate boiling a solution of sodium sulfite with sulfur and filtering the product.

The results were very nice, no spots at all, very clean negatives, like this one

Coffee+Vit.C + Sodium Thiosulfate fixer

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