Hi!

I have only owned speedlites for a week and a bit - take that as an indication of my speedlite knowledge repitoire. I do read a lot though. Here is the question:

I have a PC sync cable that I use to fire a 580EX II. I am shooting with an XSi (damn 5D2 backorders), so I used the Nikon AS-15 hotshoe adapter. The system works great to trigger the 580EX II off-camera (without ETTL of course).

When I set the 580EXII to master mode, and my 430EXII to slave mode, everything works great when the 580 is camera mounted in ETTL mode. When I take the 580 off camera and trigger it with the PC sync cable, I get some wonky results. The 580 frashes right on time, providing the beautiful light it provides. It also still triggers the 430, but the 430 goes off a good half second later (and no matter what I change, I can't alter the delay). What I don't understand is why I'm seeing the latency in the 430 firing, when there is no latency when the 580 is camera mounted in ETTL mode.

Is it possible to use a 580 to trigger a 430 when the 580 is first being triggered via PC sync?

Thanks for the help, smart ones!

John

(P.S. I have some cheap third-party RF triggers on the way anyway, but this still irks me!)

You need to be using an Off-Camera ETTL cable for them both to be firing at the right time. Using a PC sync cable will only sync with the master, the slave will just respond saying it can see the signal, but will not flash with exposure information, since you are not using the 580EX as a true master . . .

Hi, thanks for the reply!

So even if ETTL is turned off on them both, I'll still hit this problem? I suppose I assumed a trigger is a trigger is a trigger, especially in Manual mode..

You are trying to pound a nail with a screwdriver; using the tool for a task its not designed to perform.

The Canon system is designed to function with a 580ex in Master mode IN THE HOT SHOE, or connected to the hot shoe with an OC-E3 cable, which is designed to allow the Master to be mounted on a flash bracket or held overhead (which is a recipe for dropping camera, flash, or both sooner or later). The Canon Master flash communicates with the slaves via digitally coded pre-flash signals. All five pins in the hot shoe are need to exchange commands and exposure information between the camera and flash.

See this tutorial of mine LINK which will explain how to use the Canon wireless system a bit more clearly than its explained in the manual...

There is logic to the Canon system which you might not grasp yet. Whenever a flash is moved off axis it will create shadows. Those shadows, if not filled with another flash, will be harsh and distracting. The ideal position for fill flash is over the camera. Thats where it is in Landscape mode, but when the camera is turned to Portrait mode it creates an unflattering sideways nose shadow and halo head shadow.

About 50 years ago wedding shooters discovered flash is more flattering if its kept 12-18" above the camera at all times, which was why flash brackets came into use. That position is also ideal for fill with a dual flash scenario. While using a flash bracket might seem cumbersome, its actually easier to keep the fill on the camera over the lens and have only one light stand to deal with versus moving two stands and lights around.

Chuck

Hi Chuck!

Thanks for the reply! I understand your point very much, and I appreciate the link to the lighting help (I especially like that DIY diffuser).

My problem lies in shooting with both lights off-camera. I don't want to buy the IR transmitter. Consider, for example, trying to take water droplet shots with a flash on the left and a flash on the right, or consider a situation where you are trying some out-of-the-ordinary strobist angles on architecture or products (think buildings or large products like houses or tractors). I could provide more examples, but I'm sure it is easy to think of other scenarios where having both off-camera would help.

Perhaps an easy solution would be the hot-shoe extension cable, modified DIY with the ethernet cable jacks for extendability (google it). Either way, as I mentioned above, I do have simple RF triggers coming that should help with those odd setups (everything else I'd just use the built-in wireless trigger).

Thanks again for the comments and suggestions!

John

The first time you trip over the wires and flash or camera crash to the ground you'll understand why Canon designed the system to be wireless

Simple triggers cripple the flash and make it less convenient to use. Sure you can put the flash 100 yards away, but you also need to travel 100 yards to change its power, vs reaching up and turning a dial. Radio Poppers have the advantage of retaining the full function of the Canon system, simply acting as a radio repeater for the coded flash signals. The new PW system takes a different approach and have a more complicated set-up and user interface.

Because the range of a digital sensor is so much shorter that most scenes there are very view situations where some level of fill from the direction of the camera isn't desirable. The way you use flash to fit the scene to the range of the sensor is to shoot into the shadows of the dominant light source (either natural or flash) then independently control the amount of light coming from the direction of the camera.

If you want two flashes off camera a solution is to use a third flash in the hot shoe as Master, set to disable the main flash. Expensive yes, but no much more than you'd spend for a set of three radio triggers, plus you'd have a three flash solution instead of just two.

Thanks again! You seem very passionate

John

cgardner wrote:
If you want two flashes off camera a solution is to use a third flash in the hot shoe as Master, set to disable the main flash. Expensive yes, but no much more than you'd spend for a set of three radio triggers, plus you'd have a three flash solution instead of just two.


Or use a Canon ST-E2 Transmitter (slightly cheaper).

One other option is to use the 580 on the PC cable as you've been doing, and then mount the 430 on an inexpensive hotshoe adapter with built-in photo slave. Turn both flashes to manual mode, and they'll fire in sync.

It's not as flexible as having true Master/Slave capability with ETTL metering, but it's an inexpensive place from which to start until you can add more gear.