Phil Davis described his light source on Compuserve (he seemed quite serious
and I seriously doubt he was pulling anyones leg). He said his light
bank consisted of 17 18" Cool White tubes spaced as closely as possible.
I imagine they are also quite close to his negative. He claimed exposure
times with hand coated Platinum/Palladium at about 10 minutes. 17 tubes
is a lot of tubes and 10 minutes is longer time than I get from my 7 18"
32W BL tubes (I average closer to 3 minutes and my tubes are about 5" from
my negative).
John Sparks