Quote Originally Posted by HumbleP View Post
Thanks Paul,

So I tried your suggestion with a bit of colour neg. When you say "until clear" do you mean until all the emulsion has stripped off or until it becomes opaque?

Emulsion stripped off? Is that battery acid fixer you are using?

I just took some hypo+ammonium sulfate fixer I mixed a LONG time ago. A snip of color film didn't change significantly in an hour of bath. I then tried some B&W, and although I was busy and not watching the clock, it certainly cleared up in less than 15 minutes. Coulda been three. Or a tiny fraction thereof.

If you are bent on using hypo, I guess you will have to do your own testing. If you looked at the material in the links I provided, you should be able to narrow things down somewhat. Since it's hard to overfix, consider time to be the price of sticking with hypo.