I work in a venue where we have CEM+ racks with both dimmer and relay modules, as well as a sine wave rack. I have no performance issues, but noticed in the manual the different dimmer curves. Off the top of my head I assume linear would be best (the majority of our fixtures are Source Fours, with some arc and tungsten movers) but wonder if a Square or Modified Square law curve is actually better. Any opinions are valued!
Mod-square is the better choice for incandescent lamps. It tends to yield smooth changes across the entire dimmer range.
Square gives quicker response at the low end. Some designers like it; others think it is doesn't provide enough control at lower levels.
Personally, I wouldn't use linear for a Source Four since too much of bottom end of the dimming curve produces no visible light. YMMV.