Quote Originally Posted by MDR View Post
You forgot Cadmium, Lithium, etc Bromide I believe that the choice of bromide somewhat influences the lifespan and contrast of the emulsion this is at least the case in the wetplate world. Cadmium was the preferred Bromide because of the keeping qualities of the emulsions. Ammonium ads a little speed but lowers the lifespan of the emulsion. Sodium and Potassium Bromide should be about equal at least according to older literature. It's also important to know where the formulas were created for example German formulas (Agfa) liked their potassium bromide because it was readily available. Economy does play a role in the choice of ingredients.
I've been trying to think of ways that 'interested-but-not-ready-just-yet' people can participate in the discussions. You've given me an idea. I have no idea if it has legs, but it might be worth a try.

Everyone has access to the older literature. Maybe a real book, or more likely the internet. Maybe we could share interesting facts, quotes, and history. I had no idea cadmium was preferred for its keeping qualities. I wonder if that's also true for silver gelatin emulsions. What I know about relates to emulsion color and characteristic curve control.

The only potential downside I can think of is that this might turn into dueling references. Cross that bridge if and when necessary. Fingers crossed.