Nice collectors idem, I'm not really as old as this sounds but I've used them.
I also have a lot of experience with a packard shutter.You squeeze the bulb with you thumb over the hole in its tip and the air pressure goes down the line to a piston that raises the shutter open, you then estimate in you mind or count the exposure length, then release your thumb holding the pressure and the piston drops shut.
I poured the emulsion on a spinning glass plate the centrifugal force of the spinning plate spreads the emulsion evenly then baked it dry under UV light.
This experience and a lot like it make me appreciate digital.

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