inverted ISL

The inverted ISL curve works backwards, with the highest level being off, and the lowest level being full.  If two dimmers are assigned to the same DMX channel, one set to ISL and the other set to inverted ISL, they will smoothly cross-fade LEDs as the channel level changes.  (Note that in this case it is not possible to turn both LEDs off.  To overcome this, separate DMX channels would be used.)