Re: Foxlee Gum Process

Katharine Thayer wrote:
>

> What it seems to me you are arguing is that Marion got a dark reaction
> and Galinksy didn't, because Galinsky didn't have enough dichromate and
> moisture left to produce a dark reaction.

But this doesn't even work, because if the unexposed gelatin didn't wash
away, as you were arguing earlier, then Marion shouldn't have got an
image if it's the dark reaction that's responsible for the image; the
gelatin should have just insolubilized throughout. In fact this was
Galinsky's question in the first place; she wrote that if the true
explanation for Marion's observation were that once action was set up by
light in a dichromated gelatin film this could induce the same change in
gelatin placed in contact with it, then it seemed remarkable to her that
"the outline of the image would be preserved, since one would expect the
change to occur in the unchanged material around the exposed parts. It
seems more probable that the change is purely mechanical." This is why
she repeated the experiment without the pressure.

As to exposing to maximum insolubility, perhaps we mean something
different by this. When I expose a print, I expose to maximum
insolubility, so I assume that others do the same, and that Marion, for
example, did the same, as well as Galinsky.
 
kt
Received on Thu Jun 24 13:18:02 2004