neal: Umm... on a disposable camera from the dollar store It was ISO 200 film. I just developed as as normal, 1+9 and ~10 minutes, but I wasn't terribly careful.
The only colour correction I did on them is what my scanner does automatically. I was expecting less colour. If I scan them in gray scale they almost just look like really badly exposed b&w photos.
The colour will come from the coloured colour couplers (!) that would have formed the two masks had the film been developed in C-41 (these masks have to survive the trip through the fixer) and possibly some of the fitration layer(s). Some colour films use colloidal silver as the yellow filter layer.That will survive in fixer during the normal fixing time, but not in bleach - which isn't part of the normal B&W negative process, of course.