I found very little documents on the sizing process; there are plenty of howtos on most processes, but they usualy contains phrases like "size the paper then.. blah blah" without details on how to do it. Anyway, I picked some Gelatin (food grade, "Contains Sulphur Dioxide") and I was wondering if I could make a "unisize" which would allow to me use the same paper for all the processes I do at the moment. Cyanotypes, Vandykes and Salt Prints. I was thinking of making a gelatin mix containing both sodium chloride and citric acid, and I was wondering if using that size would be detrimental to Cyanos and/or Vandykes/Kallitypes.. + Any suggestions on dosage ? + Other ingredients needed ? (hardeners?) + Do I dip the paper, or do I "float", or do I coat with a brush ?