Wireless Flash Systems

[rmh159]

Could someone explain how wireless flash systems work, what equipment is needed to set one up, etc.

A friend sent me a link to a device that you can attach to any flash to make it a slave but I had thought you needed another flash that could be set up as Commander (or the in-camera flash if the cam supports it) that would trip the flash.

I know wireless systems suffer from the problem that any random Schmoe with a P&S can turn on the flash and then trigger the remote flash. Does that mean a Commander isn't needed or does the Commander use a pre-flash to set-up the remote before it actually fires it???

I know the SB-800 can trigger the SB-600/800 remotely but would devices like the one linked above make it possible to trip ANY flash with any other flash?

 

[Big Mike]

That is an optical slave trigger...so any flash that fires will trigger it to fire the flash that it's attached to.
So yes, you do need another flash to be the 'master'. I think the Wien one has an option for it to ignore the pre-flash from camera's built-in flash or any flash that uses a preflash. Cheaper slave triggers don't ignore the preflash, so can't be used in combination with dedicated E-TTL flash units.

Either way, the remote flash is not remotely controlled...it is just fired. You set the power then set it up and trigger it. If you need to change the power, you need to physically change it.

There are other options. Both Canon & Nikon have IR wireless systems built in to some of their flash units. In this case, you need a master unit and a slave unit. The master unit fires the slave or slaves and can also control their output. Also, the flash output is measured and controlled via in-camera E-TTL metering. (That's how Canon works anyway).

There is also the option of radio slave triggers. The good ones are made by 'Pocket Wizard' and there are cheap 'made in china' ones on E-bay. They are similar to the optical trigger in that you don't have remote control of the flash power...but they are not triggered by every shmoe with a flash.

 

[BAB]

In a nutshell, the link you referenced show's a unit that attaches to the flash. It is indeed triggered by another flash as when it's sensor detects a flash, it sends a signal to the flash you are using as a slave to flash, just as if it was attached to your camera's hotshoe. The more sophisticated units utilize a radio frequency to signal the slave from the commander that is attached to the camera. This design among other virtues prevents in most cases tripping your flash unit(s) by outside sources. It would essentially take another radio frequency unit set to the same frequency to set off your slave(s).

 

[rmh159]

Good stuff, thanks.

 

[rmh159]

This question might be more for Nikon-folk but if I'm understanding this correctly... I can switch the SB-800 to slave and trigger it with the on-camera flash of the D50 but all I'll get is the flash. Does anyone have a link or could explain how to set that up?

I know I'd lose the CLS-love but I'm very much a flash-newb and I'd love to start diving into this and developing my lighting skills.