Does optical flash trigger need to "see" off camera flash to fire?

[wideangle]

I have two questions relating to getting an off camera flash to trigger.

1. Cameras that have the ability to trigger (optically) an off camera flash, will the camera be able to trigger a flash that is being shot through a softbox or an umbrella? Does the camera hot shoe flash need to be able to "see" the off camera flash in order to trigger it?

2. What is the cheapest way to hook up an external flash to a camera so that you can guarantee it triggers with a cord, are there better cords than others?

[Wayne]

I know that the Nikon CLS system (optical) will trigger an SB-900 in a softbox from the camera in-built flash and from an Elinchrom head.
If you just want trigger only from the optical slave, most any flash will fire when it "sees" another fast flash.

A sync cord is the most reliable method of firing an off-camera flash, and if the flash supports i/eTTL, you should retain that if if the cord has a hotshoe, but if it's a simple PC sync cord, full manual only.

It would help somewhat if you told us what you are using exactly, and we can go from there.

[peterb666]

No. My Nissin flash units seem pretty clever in picking up the master flash from any bounced light, even behind the camera and facing in the opposite direction.

[wideangle]

No. My Nissin flash units seem pretty clever in picking up the master flash from any bounced light, even behind the camera and facing in the opposite direction.

Thanks for your replies. Might just be worth giving it a go to see if it works then apply a sync cord if all else fails.

[JPDV]

It should not be a problem: I have used the Nikon system with relatively low end branded flashes (SB 600) for a few years. I was initially surprised by just how 'hidden' the off camera flash could be from myself and the camera, yet still work: around corners, behind subjects, behind props - all fine. I'm not completely clear on the physics, but it seems to me that (for this system at least) what the off camera unit's sensor is interested in is the correct code fired by the commander - and that code gets to it whether direct from the pulsing commander, or as a result of the changes in ambient light hitting the sensor as the pulse lightens and darkens the room...Hope that makes sense(!) Bottom line - it's much more flexible than I anticipated, to the extent that I've never felt the need to go pocket wizard as a happy amateur... Range good enough for any indoor shoot I can visualise. The only downside is outdoors in bright sunlight - range and reliability drop off a little. I work with a D300 and up to 3 SB600s. HTH.