Triggering 2 cameras simultaneously

Kaouthia

Kaouthia

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So, I've decided I need to produce more "behind the scenes" images of the shoots I do for clients.

I don't always have an assistant with me, and even when I do they're not always even available to operate a second camera during the shoot.

So I got to thinking about these RF-602 triggers FITP has for sale. I know he says he's not convinced of their wireless shutter release capabilities, but there's a Yongnuo group on flickr that seem to be quite pleased with the device overall.

I do my shooting (generally speaking) with an SB-900 mounted on the body, acting as a CLS commander to several other SB-900 flashes in various light modifiers. Each time I take a shot, I'd like it to automatically trigger a second body (locked off on a tripod, wide lens, somewhere in the background covering the me, the model, assistants and the entire setup).

Having a look at the RF-602, the transmitter on the hotshoe doesn't seem to have the option to act as a "pass through" so that I can mount an SB-900 to it to keep acting as a CLS commander.

So, I'm trying to figure out if there's away around this either using the RF-602, or some other hardware, to trigger a second body whenever I press the shutter release on my main body.

If I used CLS in manual mode, rather than iTTL, there's no preflashes. So I have considered the idea of possibly mounting the RF-602 transmitter on an optical slave trigger, which would then trigger the receiver to fire the second body. If this would work in reality I have no idea as I own neither the RF-602 system nor an optical slave hotshoe trigger.

Does anybody out there have the appropriate hardware (2 Nikon bodies, couple of CLS compatible flashes, RF-602 set & optical slave hotshoe trigger) to be able to test this theory out for me?

Or has anybody out there actually done something like this before and can recommend alternative hardware to make it work?
 
But then I'd lose CLS.

The SB-900 that's hot-shoed to the camera is working as the commander to trigger several other flashes in different groups.

If I went with 1 transmitter and 2 triggers, I'd then have to put all the other SB-900s into regular plain SU-4 (optical slave) mode to be able to be triggered. But also then I'd have to physically go around to each flash to adjust power settings manually, rather than doing it from the camera.

That's why I thought of having manual power flash control (but retaining CLS so I can do it all from the camera body - manual power so that iTTL preflashes don't accidentally trigger the second camera too early), and just popping an optical slave trigger onto the transmitter. I just don't know if the transmitter will work this way.
 
Easy :) Works for me with Canon 40D and 580EX guns. Retains full auto iTTL flash. FITP sells the extra connector cable you need.

Set up your cameras normally. Plug RF-602 transmitter into camera's PC sync (flash) socket. Plug receiver unit into the remote release socket of the second camera. Job done.

The two cameras will not fire exactly in sync though, as the second camera is not triggered until the first one has actually fired the flash. This might work for or against you, depending if you want to utilise the same light from the flash/es with both exposures.

You could do that easily enough (in theory!) if you needed though, with one more receiver unit on the main camera and firing that with the manual button on the transmitter, which would also trigger the remote camera at the same time. Flash sync might be hit and miss though - should be okay I guess if both cameras are identical models and you turn down the x-sync speed a notch to make sure you catch it.
 
the second cam will trigger AFTER the first curtain goes across so could miss all or some of flash exposure, might be worth a little reccy to see how this works with flash, natural light I'd defo do it

if you hook the tx to the pc port (I got a pc-pc cable with mine) then wrap the cable around the sb (or somewhere else out of the way) it won't affect cls at all (for the trigger body at least)
 
HoppyUK said:
The two cameras will not fire exactly in sync though, as the second camera is not triggered until the first one has actually fired the flash. This might work for or against you, depending if you want to utilise the same light from the flash/es with both exposures.
Click to expand...

That actually might work out better.

I can use the popup flash in the D200 working as a commander too. Set my aperture as wide as possible yet keeping everything in focus, bump the ISO up a couple of stops, and have it trigger all the flashes again that I just used, plus an extra couple at the back to light up the rest of the scene.
 
What might work is one of the Nissin ttl cords that have two hotshoes

nissin-sc-01-universal-off-camera-shoe-cord-lrg.jpg


with the SB-900 on the one directly above the camera hotshoe and the RF-602 trigger on the other...
 
easiest way would be to set up the second camera as the trigger for the camera with the SB900/CLS setup. adjust the SS on the second camera until you are getting the full flash burst at a guess, maybe 1/100th might do it? (I don't ever use CLS so don't know what delays are involved).
 
Ok, looks like the Nissin SC-01 cable is out. That little grey switch tells the cable which hotshoe to enable. It seems it will only enable one at once, not both.

As far as using the second camera to trigger the lights, that isn't really much use. I need to have the SB-900 on the camera that's actually in my hands so I can tweak the lights throughout the shoot, and the other camera would be unattended.
 
Kaouthia said:
Ok, looks like the Nissin SC-01 cable is out. That little grey switch tells the cable which hotshoe to enable. It seems it will only enable one at once, not both.
Click to expand...

Not necessarily ;)

Perhaps you can open it up and bypass the switch :shrug:

I'm sure David will be along shortly to shoot my idea down in smoke though :lol:
 
I thought about that, but apparently it's some limitation of the way Nikon's flash system works now since they switched from D-TTL to iTTL (even if you're not actually using iTTL), unless that's just the "official word from Nikon" and somebody else out there knows better. It's been known to happen before. :)
 
You don't need the Nissin cable. The only lead you want is the Yongnuo camera trigger cord, with PC connection on one end that plugs into the camera and the other end to go in to the transmitter unit. Just let it dangle - it's very short and light as a feather.

You can use either the pop-up flash to trigger the remote guns, or an SB900. They will act entirely independently of the Yongnuos.

By the sound of it, you would probably like the option of having the second camera fire exactly in sync with the main camera, capturing the same flash illumination. As described above, that just needs another receiver unit to plug into the main camera's remote release socket.

The tricky bit will be rigging it up so that you can operate the camera properly while using the Yongnuo's manual firing button instead of the shutter release. I think that the Yongnuo's two-stage button will actuate AF and other camera functions just like the shutter release - just a bit of a fiddly practical problem.

The other thing is whether or not two identical cameras will actually sync up exactly, with the necessary mechanical precision. I'm guessing that dropping the shutter speed will do it (you'll have to do that a tad anyway to cover the Yongnuo's slight delay) then if one camera is fractionally faster than the other, putting the controller flash on the other body might sort it - milleseconds matter :D

One more thing. If you go with the first method which puts the two cameras out of sync, you could have each camera firing its own set of flashguns independently, just a few hundredths of a second apart.
 
HoppyUK said:
The tricky bit will be rigging it up so that you can operate the camera properly while using the Yongnuo's manual firing button instead of the shutter release.
Click to expand...
Yeah, I don't think that's gonna happen handholding with a 70-200VR. ;)
 
rofl. ;)
 
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