I gave up trying to use the sun to expose the contact prints. At this time of the year in the UK, it is too unreliable and when present, very variable. Some of the cyanotypes I was producing via this method were taking over an hour to expose. The alternative? A small sun tan lamp, intended for just your face, but it produces loads of UV. I tried it with the lamp stood upright and the contact print placed on the floor about 12 inches in front of the lamp. I exposed it for 20 minutes, moving the lamp around to make sure that it "cooked" evenly. The resulting print (shown below) is OK, but not evenly exposed or exposed enough. [This print has a second probably which is due to washing marks on the image side of the print. You can see these in the top left corner. Good news is that I have managed to work out how to dry the prints flat.]
I tried a second print with the lamp suspended horizontally over the contact print (about 4 inches above). I exposed it for 40 minutes. The results? Massive over exposure and almost no image at all. Didn't even both washing it. It went straight in the bin.Now, I know better than this. I should have kept all the variables the same and just changed one. Changing the distance of the lamp from the contact print AND the amount of exposure time was bound not to work. Stupid mistake.
When all else fails, go back to first principles.
OK, next step to create a method of exposing the contact print in a constant manner and produces some test strips at different timings.
