Photography Online 1st shoot with glass plate

Thanks for sharing. Very interesting to see how fragile the wet Zebra plates are.
 
It's almost exactly 40 years to the month since I last made and coated photographic emulsions for commercial use, normally you add adjuncts like hardeners prior to coating. For basic hardening typically Chrome Alum, and Formalin, are added, the actual level is extremely low, but very effective.

There are ways of coping with poorly hardened plates, or films. First add a hardener to the developer, second use a hardening stop bath, third use a hardening fixer. Or use a Pyro tanning developer as they harden the emulsion during development, and Pyrogallol was the developing agent used with very early Silver Gelatin plates.

ISO 2 is a bit slow, I'd guess the emulsion I made was ISO 6, I did make faster while researching, but base fog rises slightly , and that's fine for film use, but the emulsion I made was for projection printing. Speed & Contrast was almost identical to I
 
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