Trigger 2 cameras at the same time...problem

[Bend The Light]

Hi,

I recently bought a RF602 Yongnuo trigger and reciever. I want to trigger both cameras at once to play about with stereo images. But I want to do it in the studio with studio lights...

I tried tonight and had problems, so here's the set-up...can you say what's wrong?

400D - has the Yongnuo trigger on. This is the lead camera, if you like. But with the trigger on the hot shoe, I can't put the lights to the 400D

40D - has the lights in the RF socket. Also has the receiver which has a cable to the trigger socket.

So, theory is, the 400D shutter is depressed, the 400D AND the 40D shutters are activated, the 40 triggers the flash via the RF socket.

Now, all this "worked"...both shutters fired, and the lights fired. but the 40D had a well exposed image, and the 400D had an underexposed image, as if it had "missed" the lights. Now I reckon there must be a delay, with the 400D shutter activating, and closing again before the 40D is triggered along with the lights.
Does the Yongnuo trigger have a delay? Is there any way around this?

I am getting another RF602 receiver soon, so will trigger both the 40D shutter and the lights on the same trigger signal. Would that solve it, do you think? (actually, I will have it so the 400D is the "slave" camera as I am waiting on the relevant cable for that too).

 

[DizMatt]

what settings are each camera on? related to sync speed etc
if you set both shutter speeds to 1/80 or similar (as shutter speed isn't as important in the studio iirc) and set them to end curtain, would that make a difference?
let the triggers catch up?

 

[Bend The Light]

what settings are each camera on? related to sync speed etc
if you set both shutter speeds to 1/80 or similar (as shutter speed isn't as important in the studio iirc) and set them to end curtain, would that make a difference?
let the triggers catch up?

Yes, I thought something like that, although I haven't delved into the rear-curtain stuff. I need to go again and try longer shutters etc. Only problems come with ambient light if the speeds are too low.

The stereo stuff aside, I would also like to have the 400D recording Behind-the Scenes stuff while shooting hand held with the 40D. I need them to sync with higher shutter speeds, especially when shooting kids etc.

I will keep trying, and I have another receiver coming soon so maybe that will help. Trigger both shutters in the same way, as "slaves" rather than having one be the master and one the slave.

We'll see.

 

[HoppyUK]

I think you mean PC socket rather than RF, but no matter.

To make it all work in perfect sync, you need:

Transmitter in the 400D (slower camera) hot-shoe and a receiver plugged into the remote firing socket of the 40D. The two camera will fire virtually simultaneously, only the different shutter lags between them, therefore slowest camera first.

Second transmitter in the 40D hot-shoe on a different channel, and receiver plugged into flash.

The only thing you've got to juggle is the shutter speed, to make sure both shutters are fully open when the flash fires, due to lag. Suggest 1/100sec. If you get a dark band at the bottom, go slower, but you might get away with faster.

Edit: thinking about this for a mo, the second camera will probably have quite a bit of lag. The flash will be simultaneous, but you might have to run quite long shutter speeds to catch it with both. Depends what you're doing and how important shutter speed is, ambient etc. To get the cameras closer in sync, you'd need to trigger them both simultaneously with a hand-held transmitter and receivers on both, but being different models (40D has much less lag) you can never get them perfect.

Suggest you work around this problem by eliminating all ambient light, then it doesn't matter. Is that possible?

 

[Bend The Light]

I think you mean PC socket rather than RF, but no matter.

To make it all work in perfect sync, you need:

Transmitter in the 400D (slower camera) hot-shoe and a receiver plugged into the remote firing socket of the 40D. The two camera will fire virtually simultaneously, only the different shutter lags between them, therefore slowest camera first.

Second transmitter in the 40D hot-shoe on a different channel, and receiver plugged into flash.

The only thing you've got to juggle is the shutter speed, to make sure both shutters are fully open when the flash fires, due to lag. Suggest 1/100sec. If you get a dark band at the bottom, go slower, but you might get away with faster.

Yes, I mean PC. Where'd did RF come from?

I did have the reciever on the 40D and the transmitter on the 400D. They didn't fire simultaneously, though. That's the problem. The 40D was later, and it was the 40D controlling the lights as in your example. The only difference was that the 40D was controlling the lights from the PC socket not another trigger (which I don't have).

I know I will have to juggle shutter speed. That's ok for still life, or me posing, but another thing I want to do is shoot handheld with the 40D and have to 400D doing BTS shots at the same time. It needs to be simultaneous to do that...

Have another receiver coming, and a couple of relevant cables to trigger the 400D as well, so will go back and try that.

Thanks for the input.

 

[HoppyUK]

Yes, I mean PC. Where'd did RF come from?

I did have the reciever on the 40D and the transmitter on the 400D. They didn't fire simultaneously, though. That's the problem. The 40D was later, and it was the 40D controlling the lights as in your example. The only difference was that the 40D was controlling the lights from the PC socket not another trigger (which I don't have).

I know I will have to juggle shutter speed. That's ok for still life, or me posing, but another thing I want to do is shoot handheld with the 40D and have to 400D doing BTS shots at the same time. It needs to be simultaneous to do that...

Have another receiver coming, and a couple of relevant cables to trigger the 400D as well, so will go back and try that.

Thanks for the input.

Crossed post - my my edit above

 

[Bend The Light]

Crossed post - my my edit above

Thanks. Yes, we're coming to the same conclusions. I need to et more practice and see what I can do...especially with the second receiver.

Cheers

 

[JonathanRyan]

I don't think this is going to work like this.

I've used dual cameras on RF602s but there's a propagation delay and I've never got them both to work with flash.

Shooting available, the remote one will fire about 9 fps to the main one's 11 with cameras that should both sustain 11.

Can you trigger them both via a splitter cable? Should sync the shutters exactly. Alternatively....2 flashguns?

 

[Bend The Light]

I don't think this is going to work like this.

I've used dual cameras on RF602s but there's a propagation delay and I've never got them both to work with flash.

Shooting available, the remote one will fire about 9 fps to the main one's 11 with cameras that should both sustain 11.

Can you trigger them both via a splitter cable? Should sync the shutters exactly. Alternatively....2 flashguns?

I have another receiver coming, so that might help to trigger both camera simultaneously. Just have to work out how I can do it and not have to have the trigger in my hand...I may want to move the main camera about and use it handheld...

Thanks

 

[JonathanRyan]

I have another receiver coming, so that might help to trigger both camera simultaneously. Just have to work out how I can do it and not have to have the trigger in my hand...I may want to move the main camera about and use it handheld...

Thanks

I've seen people tape triggers for second cameras to the lens barrel. Then you can press it with your left hand.

 

[Bend The Light]

I've seen people tape triggers for second cameras to the lens barrel. Then you can press it with your left hand.

Hmmm...there's a plan.

 

[eagercat]

Hi there BTL, Your Stereo images will not work. Tho` if your eyes are a few feet apart you stand a chance, LOL The space between the two camera lens should equal the distance between yor eyes. Vtech make a stereo camera for £27.

 

[Bend The Light]

Hi there BTL, Your Stereo images will not work. Tho` if your eyes are a few feet apart you stand a chance, LOL The space between the two camera lens should equal the distance between yor eyes. Vtech make a stereo camera for £27.

Wasn't placing the cameras a few feet apart. Granted they will be a tad wider than my eyes are apart, but that does work. I have done stereo images before, out in the wild, and have not constrained myself to a couple of inches apart. It just accentuates the stereo just a touch.

e.g.

rhodedendron by http://bendthelight.me.uk, on Flickr

Thanks

 

[HoppyUK]

Wasn't placing the cameras a few feet apart. Granted they will be a tad wider than my eyes are apart, but that does work. I have done stereo images before, out in the wild, and have not constrained myself to a couple of inches apart. It just accentuates the stereo just a touch.

e.g.

<snip>

Thanks

That doesn't work very well for me. I'm suspecting the wider spacing is just too much at close distance like that?

I've seen some spectacular landscapes though, grand canyon and the like, taken with cameras a few feet apart

 

[Bend The Light]

That doesn't work very well for me. I'm suspecting the wider spacing is just too much at close distance like that?

I've seen some spectacular landscapes though, grand canyon and the like, taken with cameras a few feet apart

Different people have differing success in seeing these anyway. It's people in the studio that I want to get if I can, and I think the size will make some difference...as it is, I have the cameras literally next to each other, so the distance between the lens's centres is probably about an inch or at most 2 inches wider than the set of the eyes. With the flower above, I recall a quite significant shift, possibly about a foot or so.

Anyway, we'll see.

 

[HoppyUK]

Different people have differing success in seeing these anyway. It's people in the studio that I want to get if I can, and I think the size will make some difference...as it is, I have the cameras literally next to each other, so the distance between the lens's centres is probably about an inch or at most 2 inches wider than the set of the eyes. With the flower above, I recall a quite significant shift, possibly about a foot or so.

Anyway, we'll see.

I can make it work, by doing that cross-eyed staring thing (had to reduce the size first) when it suddenly pops into 3D, but then the effect is very exagerated, looks like the flower is about a foot deep.

I'm no expert on stereo but there must be some rules/guidlines on spacing vs shooting distance?

 

[Bend The Light]

I can make it work, by doing that cross-eyed staring thing (had to reduce the size first) when it suddenly pops into 3D, but then the effect is very exagerated, looks like the flower is about a foot deep.

I'm no expert on stereo but there must be some rules/guidlines on spacing vs shooting distance?

There probably are rules, but hey...what are rules for...

 

[eagercat]

Go back to Victorian times when stereoscopes were all the rage. They are quite easy to make. I remember Woolworths sold one complete with a circular viewing card (about 10 shots) It was spectacular. If you stand on the edge of the grand canyon and viewed the scenery you would see the correct stereo effect and your eyes are only inches apart.

 

[HoppyUK]

There probably are rules, but hey...what are rules for...

Not for ignoring, usually

How about a simple stereo adapter, like this little Pentax jobbie from a few years ago? I've seen modern equivalents around http://www.t-rofilms.com/3d-stereoscopic/ Seems a lot easier!

 

[Bend The Light]

Not for ignoring, usually

How about a simple stereo adapter, like this little Pentax jobbie from a few years ago? I've seen modern equivalents around http://www.t-rofilms.com/3d-stereoscopic/ Seems a lot easier!

Not, not ignoring, but certainly for exploring the possibility of a slight "bend".

That adaptor looks pretty good...might look for one of those just for t'laugh.

Cheers