I want to try if it is possible to print with liquid emulsion (silver that is) over a cyanotype. I know that there are people that print over cyanotypes with Van Dykes or Gum bichromates... I don't know if it will work with silver or if the cyanotype chemistry won't react well with the silver developing baths... I'll run some test to check those kinds of possible problems, but still I have another problem that I should solve now.
Let's suppose I have a scan from a bw negative. I want to print the highlights with the cyanotype chemistry, while masking the shadows and - viceversa - print the shadows with another negative in liquid emulsion. The problem is: how to create two different negatives from one single grayscale image that will produce an almost correct and pleasant split-toned picture.
I've been working with photoshop for hours yesterday and I couldn't find any good trick to do that... Have tried with select->tonal range and then highlights or shadows... But then the midtones are left behind and the problem is how to create a smooth separation in between... One of the two negatives should include the shadows and let's say 50% of the midtones... the other the highlights and the remaining 50%... So when I'll try to print those two by contact I shouldn't have the same areas exposed twice, resulting in a ugly dark-gray area between shadows and highlights... I don't know if my explanation was clear enough, I'm sorry but english is not my motherlanguage.
Of course I already use digital negatives and have the right curves for both cyanotype and silver.
thanks in advance