If you set the coarce dial to say G and the fine dial to 20 it doesn't really mean any thing. It's just there so that you could remember to return to the same setting. Beseler made the module and in the module are 4 multiturn potentiometer and there is no such marking. Basically you would null each channel for each kind of analyzing mode. For example skin tone, gray card, or diffuse with a diffuser and everaging the entire negative. You could use each module per program or you can jot down the setting on the coarce and fine adjustment knobs. My newer Omega SCA 400 would automatically null when you push a button and store the setting in digital memories.
Originally Posted by paul ron
The color analyzer measures light in relative term and not absolute. It only tells you the difference in light level in relative to the null.