I'm testing out some Cranes 90# cover stock with Cyanotype and am have a real problem trying to get the images to clear in the wash. The formula coates very easily and the images look good, however, I can't get rid of the slight creamy color in the white areas in the image - even after 30 minutes of washing. Anyone have some suggestions on chemicals to use that might help the process?
I bet you are getting some fogging... reaction between the paper and the cyanotype emulsion.
Mike Ware states that the dry paper should be bright yellow, NOT GREEN!!!!in the least. What color is yours? It needs to be YELLOW, not yellow/green. He says that his formula is an excellent test for your paper's purity!
The paper color looks good. There doesn't seem to be any different of a color in the dried sensitizer than other papers that I've been using. I'm not discounting the fact that there might be just enough of a fogging action to cause the color problem. However, if that were the case, wouldn't the coloring be somewhat on the greenish/blueish side. The color on my paper is definitely cream with no apparent trace of blue or green in it.