Quote Originally Posted by Tom1956 View Post
Having followed this scholarly treatise on print washing, understanding most of it, I have a question from the point of view of the Kodak customer--the guy who just buys (bought) the products on the camera store shelf. And I'm bound to ask if the washing instructions Kodak gave 40 years ago aren't still adequate today. Those instructions being Dektol, ISB, Kodak Fixer, HCA or Perma Wash, then an hour or so of washing in a rotary washer, for DW paper. Is there really that much advantage in the alkaline fixer and trying to flush out mere molecules worth of hypo for all that procedure? At some point, the image will either fade, dry and flake off, or the paper underneath it will turn to dust, whichever comes first. Is there really such an advantage in this hair-splitting procedure?
Pretty much. Things that make a wash more effective do not necessarily allow a shorter wash time. With double weight papers, the slow down in washing effectiveness after initial removal of hypo from the gelatine is pretty pronounced, and it takes time to get the thiosulfate out of the paper fibers. A one-hour wash, even without HCA, reduces the thiosulfate to generally acceptable levels. HCA can reduce the wash time some - see the instructions, but a one-hour wash is still a good guideline.