Reading other threads concerning UV print times for various processes it seems that my times are much longer than might be expected, particularly salt prints. They are at present taking anything up to an hour or more. The actual time is more as I have to stop every 15minutes for the contact printer and glass to cool down.
I am using FP4+(PyroPMK) in a frame I made myself which has 6mm Pilkington Optiglass (expensive but, so I was told, has better UV transmission). It IS quicker than ordinary glass!
Attached is a picture of my printer which I made and is fitted with 8 x 15w (total 120w) Philips F15 T8 350 BL UVa tubes. They are about 3inches from the frame glass which measures 11x14 inches.
I am wondering if anyone might have some idea as to why this setup is taking so long to make a print. Should I remove the inner frame which supports the print frame; I don't really see that would make any difference. Another might be to have stronger tubes but that would, I'm sure, only heat everything up even quicker. I could use thinner glass but with the times I'm experiencing now, I can't imagine any great reduction in time would be achieved.