I, as many others as well, used this method for years back when these printers with postscript capability for controlling halftones, looked like a great substitute for the actual photographic process. There were specific vellum papers that took the toner well, yet still often needed help from spray lacquers, clear enamels, hairspray, or specifically marketed "toner aids" which would darken the result by slightly melting the toner particles further. A trip through the dryer could do this as well, but would nix any chance of tight registration on multi color jobs.
Ink jets, along with a RIP took over this niche, with better d-max density, lower d-min with clear or almost clear media, and better shaped dots.
