Hi, Sid,
I need to trigger a Canon 580EX optically, not by using IR, and not pocket wizard.
The main lights is a studio strobes, so there is no requirement to deal with pre-flash.
Do you mean that the studio flash units will be electrically triggered by the camera, and you would like a 580EX to follow along, triggered by their bursts?
A 580EX can be triggered (in its manual mode) by a conventional optical slave trigger unit, but . . .
The but is that, for example, the 550EX cannot be triggered this way by certain types of optical triggers owing to some lockup phenononon at the sync interface. For example, it cannot be triggered by the common variety Wein "shoe mounted" optical trigger.
I have no ideas whether this is so of the 580 EX or not, nor which models of optical trigger units produce this anomaly (I only have one, the type I mentioned above).
Then 580EX cnanot be set to, by itself, respond to a plain flash burst. It can of course be triggered in the Canon wireless flash system by commands issued by another 580EX, a 550EX, or an ST-E2 Speedlite transmitter (on the camera).