oxide or sulfide

[joho]

a matter of tone - what selenium is used in selenium toning ?? oxide or sulfide or Selenium trioxide ??

[Bernard_L]

Most detailed account that Iknow of:
https://www.largeformatphotography.info/forum/showthread.php?106341-Selenium-and-Tellurium-Toning

Sodium selenosulfide, NaSeS, or sodium selenosulfate, NaSeSO3, are believed to be the active toning agents in many selenium toning solutions.

[MartinP]

IMPORTANT: Also remember that mixing the stuff from dry ingredients on the kitchen table is a serious way to kill your nervous system. There was at least one London professional printer in the seventies who died a very slow and unpleasant death in his fifties, by trying to make the 'ultimate toner' manually for several years. I am trying to remember the guy's name but failing -- he had his darkroom in a cellar IIRC.

If you want to make a special toner, talk to Moersch and ask them for advice. They might even already have a product off-the-shelf which you can use or tweak a bit.

[jnantz]

hi joho

if you run into a dead end there are some liquid selenium toners out there that might be of some help.
good luck with your search!
John