is it possible to "dim" a MH bulb like you can, say a reg 60W bulb?


what I mean by this is:

if I built a controller to turn my lights on and off, could I ramp up the voltage over a half hour from "off" to "full on" to provide a "sun up" effect, and then in the evening do the exact reverse to provide a "sun down" effect....

the reason I ask is does a MH need FULL POWER ON to light (like florescent bulbs do) or are they more like standard bulbs?