what is the difference between the "old school" cold light source diffusion head and the modern diffusion light source with those dichroic filters for adjusting the contrast of thelight source. Currently I'm happy using the condenser head and VC filters. Nothing wrong with touching up dust spots with a good brush on a final print. Reluctant to try the aristo cold light head for my D2V because my understanding is that they were meant for graded, not variable contrast filters. So I'm just at a quandary because when people mention diffusion light sources its generally the modern ones. Can anyone with knowledge suggest how to go about trying out my cold light source without setting myself up for disappointment? Tall order I know but I'm a patient man.
The older Aristo (and Zone VI) cold lightheads produced a bluish light which suited graded papers. Some people found that using VC filters with this head gave unsatisfactory results, but some people seemed to manage. Aristo more recently made a replacement tube with a wider spectrum which suited VC filters. Aristo was taken over but the new company still produced the new tubes on order. Search Photrio for Ken Nadvornick and Aristo. I don't know if the new company is still offering the tubes. It's rather old technology and companies move fast.
The new company also made replacement tubes for the Aristo VCL4500 two-tube VC head. I have one and I did get some replacement tubes from them (at significant expense!)