I have been researching dimmers so I can do my own dmx dimmer. There appears to be 2 methods using Phase Angle.
In breif once zero crossing is detected, you either turn the triac ON or OFF.
After an ammount of time determined by the dmx channel value the triac is turned OFF or ON.

My question is: should I turn the triac ON at zero crossing and then OFF, or should leave the triac OFF for a period of time and then turn it ON.? I would image the latter will have substanial turn on spkies.

Cheers
Matt