Sensitivity Of Wet Vs. Dried Dryplates

[wildbillbugman]

It has been my observation that while coating glass plates one can "get away" with enough yellow safe light to see what one is doing. However, once the emulsion has dried, the sensitivity goes up such that I must work in the tiniest possible lighting. I used to work in total darkness with Night Vision Manacles. However, due to poor depth perception using one eye only,I had too many spills. Night Vision goggles that use both eyes are expensive.
My question is: Is my observation that dry plates are more sensitive after drying than before drying a valid one?. All of my emulsions are intended to be panchromatic and contain dyes.
Bill

 

[Photo Engineer]

Bill, in my experience, a wet emulsion in a beaker is less sensitive than the same dry emulsion on a plate. This is a bulk effect.

I have never tested a wet plate vs a dry plate of the same emulsion. I've just tested wet bulk against dry coating. So, AFAIK my "test" means little wrt to what you are asking, but I offer it as a thought.

PE

 

[wildbillbugman]

Thanks PE,
If I can trust my own observations, the same emulsion is more light sensitive when dry than when wet.. If someone can validate or dispute this observation, I would like to hear from you.
Bill

 

[Photo Engineer]

Bill, perhaps I should explain more.

I was melting a large beaker of emulsion (1L or larger, I don't remember), when a co-worker came in and turned on his flashlight, but he grabbed a clear light and it hit the beaker square on. It took him a few seconds to realize what he had done and then turned it off. I began to prepare a new batch, but he told me not to worry, that the emulsion was ok. It seems that the light penetration into a full beaker is very low.

I went ahead reluctantly, as I was new to this though I had no basis to argue. After coating, I had a normal coating regarding speed and fog. So, turbidity won.

IDK about your case.

PE

 

[wildbillbugman]

PE,. Perhaps the added thickness of a wet coating translates to less light at the interface between emulsion and glass.
Bill

 

[Photo Engineer]

I have no idea Bill.

Sorry.