7D triggering two speedlights Q

I would like to trigger two 430ex flashes with my 7D and expose using ETTL. Haven't bought the second flash yet but can get one used for under $200. Now the only way this appears to work is by setting the on-camera flash to ETTL (which I could trigger using manual setting at 1/64 or whatever the smallest setting is). Thus, even if I give it a low ratio, I will still have some head-on light. Is this the wrong way to approach this? The second flash would also come in handy for my XTi my wife is starting to get into. Thanks.

You can achieve this in Manual Mode.....
If you put you 7D's flash at it's lowest manual power rating (let's say 1/64 power) and set the other two flashes at what ever Manual Power Rating you want them to be (say 1/2 power on one and 1/8 power on the other), then if the other two flash are in range of the 7D's preflash, then all 3 flashes will fire..... But you'll have to seriously chimp on your exposure or use a light meter.....(LOL, then again, I just realized that that isn't ETTL) it's just simply wireless flash using Canon's Wireless IR Technology. So, to answer your question, I don't think that you can set your Master Flash (7D on camera flash in your case) to manual, and still have the Slave Flashes do ETTL. But you can do it the opposite way. You can have your Master Flash set to ETTL and have your Slave Flashes set to Manual Power Flash.

Do it in ETTL and turn off the on board flash. That way it should just act as a master for the slaves.

Thanks guys. But I really want to use the speeedlights on ETTL. They won't work unless the camera flash is on ETTL. I could go manual in a studio, but I really want the auto exposure outdoors on the move.

glockamole wrote in post #10897374
Thanks guys. But I really want to use the speeedlights on ETTL. They won't work unless the camera flash is on ETTL. I could go manual in a studio, but I really want the auto exposure outdoors on the move.

Unfortunately your need/desire is the direct reverse of the best capability of the ETTL wireless system. It works best indoors in a studio. Bright light reduces the effectiveness/reliabil​ity.

But you do understand you can do this with the 7D and not have the pop up flash contribute to the exposure, right?

just set the wireless func. to just fire the speedlights

i really like using the7d wireless feature in manual mode tho
no more needing to go to each light and setting the power
everything can be done on camera!

Thanks, guys. I guess I didn't understand how the on-camera flash can be set to not contribute to the exposure. With only one speedlight, I have to set a ratio that includes the on-camera flash. But looking at the manual, it looks like a second speedlight allows you to exclude the on-camera flash.

glockamole wrote in post #10899104
Thanks, guys. I guess I didn't understand how the on-camera flash can be set to not contribute to the exposure. With only one speedlight, I have to set a ratio that includes the on-camera flash. But looking at the manual, it looks like a second speedlight allows you to exclude the on-camera flash.

A 2nd external flash is not really necessary to exclude the built-in flash. Take a look at page 120 of your 7D manual ("Fully Automatic Shoting with One External Speedlite") and especially note step 5 which tells you how to set the camera so that the internal flash is NOT used for exposure.

PacAce wrote in post #10899223
A 2nd external flash is not really necessary to exclude the built-in flash. Take a look at page 120 of your 7D manual ("Fully Automatic Shoting with One External Speedlite") and especially note step 5 which tells you how to set the camera so that the internal flash is NOT used for exposure.

Thanks alot, PacAce. I got it working. I had read those pages a few times. I'm a bit slow. So I think I'm going to pick up another 430EX.

Just to confirm what everyone else is saying - the 7D popup flash can be set to not contribute to the final pic. To be clear - it will STILL FIRE - but this is happening *before* the exposure, and it is only there to communicate to the other lights. The human eye doesn't register it as multiple flashes - we only see one.

Two 430exII's can be triggered in this manner, in ETTL mode. I do it all the time with my 580exII and 430exII.

pcj wrote in post #10899551
Just to confirm what everyone else is saying - the 7D popup flash can be set to not contribute to the final pic. To be clear - it will STILL FIRE - but this is happening *before* the exposure, and it is only there to communicate to the other lights. The human eye doesn't register it as multiple flashes - we only see one.

Two 430exII's can be triggered in this manner, in ETTL mode. I do it all the time with my 580exII and 430exII.

To be technically accurate, the command flash will also flash when the shutter curtain is open so the command flash going off in the picture may be noticeable and will contribute, however slightly, to the overall exposure even if the master is disabled. An easy way to confirm this is to take your camera into the bathroom (without the slave flash) and take a picture of yourself in the mirror with all the lights off.