Steve and Mike it sounds like some real innovation and ingenuity is going on there. It looks very promising. I've harped enough about the absence of a head for my Durst so I'm watching this very carefully.
My postcode is PO33 2SE if you need it to work out postage cost.
I currently have a 105mm lens which appears to project the whole of the 5x4 frame but until I make a print I will not know how much light falloff there is at the edges. It would be nice to do my tests with a lens designed for 5x4 as this takes another unknown out of the equation.
I have found that the best results so far require a diffusion layer very close to the LEDs and another just above the negative. With just one or the other, I see obvious patches of red, green and blue light. With both diffusers I see a very even white light over the whole of the open area which is actually 5" x 7" despite this being marked as a 5" x 4" enlarger.
I'm not sure if my PCB is from a PAR 56 or PAR 64 light but mine also has 153 LEDs and looks very similar to yours, if not identical.
What is your distance from PCB to negative?
I have got an EST 1000N. The EST2000N does have some thermal sensor.
I do not think I need 1000W of leds see this Apug thread: http://www.apug.org/forums/forum43/5...roic-leds.html
With about 30 leds, 2 ¾ stops faster than an 1000 watt quartz halogen dichroic.