Problem with pictorico

Hi

I am creating negatives for platinum/palladium printing, on pictorico using an epson 3800 and the quadtone rip. The negatives are beautiful and print as I want. The problem is that when I go back to make another print, the negative has changed. It appears the that density of the white has changed to create patterns that show up in the print. A common example is a series of wavy patterns, running paralell to each other, across the print. Another is the creation of impression of large, erratically shaped "cotton balls" throughout the print. These do show up in the print.

I have created 2 sets of some of these negatives. I plan to use one and not the other to try and isolate the problem. They currently look fine.

I initially dry them for about 1/2 hour in a warm, circulating air, then overnight on screens, face up.

Anyone else experience this? Any suggestions?

Thanks

David Burbach

I'd take a small piece of Pictorico from the same packet that you're using and expose it to your UV light source for the same time that you did previously (for the negative that's gone wonky). If it turns out fine then there's nothing wrong with the Pictorico on its own, only when it's in contact with your coated paper (you could also test a piece in contact with a piece of uncoated paper I guess). You could then try sandwiching the negative and coated paper (using a sheet of mylar inbetween for example - or by turning the negative so that the printed side is 'up' i.e. not in direct contact with your coated paper). If that turns out ok, (and assuming your negative is dry - which it sounds like it is), then maybe your coated paper is too damp, and when you print with the printed side of the negative face down, this dampness/humidity is degrading the pictorico coating in some way.