I purchased one of the last of the Zone VI 4x5 split light cold light head for an old Beseler 4x5 MCRX back in January 2004. At the same time I purchased a Metrolux II. I have been using it as a split light source for the past year and have had a number of frustrations using it. I wonder whether anyone has suggestions on ways to correct my frustrating experience. I have been using the light system as a totally split light source in the Zone VI system and the light output is quite weak. The enlarging times for the green (soft) light are very long if the aperture is more than 1 f/stop above wide open. If I combine the lights there is no way of knowing what filter grade one is using without doing elaborate testing with each paper type used. In addition since the sensor in the light head and connected to the timer is much more sensitive for blue light than the green light, when the lights are used together, the Metrolux timing is much shorter for the soft green light than it normally would be for the green alone. Therefore, I think it makes it extremely difficult to make fine adjustments in a systematic manner when the two lights are combined. The light is too weak to be able to accurately use the probe on the metrolux to compute changes in exposure time when enlarger height is changed. I have not attempted to use the probe as a densitometer yet because it doesn't automatically help you to assess filter grades or exposure times. I end up spending several hours printing one negative before I produce a good print and waste materials in the process. If it is a difficult negative it may take me several days to produce a satisfactory print. Obviously, this is frustrating and detracts from the enjoyment of the whole photographic experience.