That's great help Trevor, thanks a lot again. I'm getting into pt/pd myself but will also be using it for cyanotypes too. How did you rig the lights up to an enlarger timer? that's a very sweet idea. My cousin is making me a 12x16 contact printing frame so an exposure unit the same size as yours would be ideal. likewise, I'd like the opportunity of printing larger than 10x8 if I wanted to. Initially I was just going to use 2 lamps with uv bulbs either side of the print, would that idea have fallen flat on its face? Could you give me the exact dimentions of the cabinet please. I'll go order the bulbs today.