Hi, right now I just use the sun to print stuff like cyanotypes and such, but I was wanting to start doing more printing, and different methods.. like carbon prints mainly. So I was considering using a metal halide lamp from a hydroponics store. My question is are the ones with horizontal bulbs suitable? Because they have complete units with a reflector and holding the bulb horizontal and ballast. Or is it better to have a reflector that holds the light perpendicular to the print? The bulb I was considering was the 400W 'blue' one by eye hortilux (MT400D/HOR/HTL - BLUE). The blue seemed to have more light in the UV-blue range. Is a 400 watt enough since I mostly contact print 4x5-5x7 negatives? Does anyone know if this bulb is a good choice? Thanks!