I have been making emulsion for a short time using the simple photographic emulsion shown on the unblinking iye site. I find that adding all the silver at once gives better contrast.
When coating large plates with Rockland emulsion it is best to heat the plate first, and if the emulsion starts to set up before it is evenly coated use a heat gun to remelt and it will even out.
In making my emulsion I have calculated that the cost for 8oz. is less than a few dollars for materials compaired to $30. for a commercial brand. It is not such a waste when you screw up a plate. But the time to make emulsion is a couple of hours or so as opposed to collodion wich only takes a few minutes.
The brand of "Glass Wax" that was used for cleaning glass for wet plate collodion is no longer made. There is still a product by that name, but it's not the same. They had to change it due to a chemical hazard issue. From what I've heard from fellow wet-heads, the new stuff does not work well for collodion. It causes chemical fogging problems.
Originally Posted by PHOTOTONE
2013 Workshop Schedule Online
Speeding up silver addition when making an emulsion generally gives a higher contrast slower result, while slowing down addition speeds up the emulsion but lowers contrast.
Originally Posted by kevin klein
This, like everything in emulsion making, is a generalization. But, the textbooks referred to fast addition as plopping or pouring it in. In German this was "gekipped" or tipped.
This is probably one of the worst ways to add silver to the halide gelating mixture, but it does work.