I would agree that spectral output and color temperature are two only loosely related scales. Generally speaking, however, an actinic (violet and ultraviolet) bulb intended for saltwater reef aquaria and vegetative plant growth (don't ask me how I know this) will work well as an UV light source for printing. I use a plain Jane GE 400W MV with excellent results. My print times for Pd using dense negatives range from a minute to around 30 minutes. Granted I could do much batter with a 1000W setup, but I had a 400W (for another use) laying around, so that's what I use.