Priority: High
<< A friend made a publicity poster using cyanotypes and kallitypes on the
same
paper. At first it looked great. But now, after two years, both are fogging.
>>
I've made a number of prints combining various processes, including kallitype
on top of cyanotype and gum and also cyanotype on top of salt prints.
You obviously get a great deal of bleaching occurring in putting cyanotype
over a silver image, but in my examples this was not complete and the result
was a noticeable shift in tone in the cyanotype giving an attractive grey tone
to the blue - particularly in shadow areas.
For the kallitype applied over other processes I applied to solution (VDB)
exactly to the areas required using a fine sable brush.
As with a number of questions, the easiest approach is often to just give it a
try and see what happens. Even the things that theory demands will not work
often turn out to give interesting results. Contrary to the experience of
Terry's friend my mixed prints are ok after around six or seven years.
Peter Marshall
On Fixing Shadows, Dragonfire and elsewhere:
http://faraday.clas.virginia.edu/~ds8s/
Family Pictures & Gay Pride: http://www.dragonfire.net/~gallery/
and: http://www.speltlib.demon.co.uk/