Bas, off the top of your head, which of the various types you mention in
your (informative, thank you) post would you start with if you had
uncontrollable urge to try cyanotype on one such? Students often ask
about "rice paper," I can say only in my experience it's harder & less
attractive than a brown paper bag (which is great to print on BTW) but I
know that's not what they're looking for.
As for the "very soft" printing paper for cyanotype I mentioned, it was
"Whatman Print," from NY Central supply at 11th St & 3rd Ave. In 12
minutes reached about step 17. The top steps were sort of veiled & faint,
but the first 15 or so had really good separation.
Another excellent soft paper was Cranes Platinum Text Wove, 13 good steps
in 8 minutes exposure.
As for the ferric ammonium citrate brown scales, I've never used it, but
books say it's *much* slower than the green scales. Am not sure the price
differential still holds in this country, BTW....
Judy