7D wireless flash trigger can't expose

[int2str]

Originally Posted by PacAce

What lens were you using? You'd need to use the 24-105 f/4 lens to reproduce the severe overexposure problem with FEL. None of my other lenses overexposes like the 24-105 f/4 lens does except for the 70-200 f/2.8 lens which does overexpose slightly but not as much as the 24-105

I used my 70-200mm f/2.8

[int2str]

Originally Posted by apersson850

I use FEL quite a lot, and especally when using multiple flashes, since then it's more difficult to quickly control the direction of the light, if the scenario evolves in an un-anticipated way.

And when you use multiple flashes, probably with modifiers etc. Have you encountered this problem?
In other words, have you ever seen this problem occur anywhere but in an artificial test setup?

I'm really wondering. I'm not trying to discredit you or anything. Just wondering if this has actually ever been an issue in a non-test setup for anybody.

[apersson850]

Oh yes, I have. Especially since to begin with, it was usually not workinig regardless of whether I used FEL or not. For some reason I don't understand that improved prior to installing firmware 1.1.0. Anyway, in the beginning I thought maybe I was doing something wrong, as the 7D was very new to me. I had a lot of experience with Canon's wireless remote system using a 580 EX II as a master. An when I put that flash on the 7D, to use wireless the same way I had to with the 40D, it worked. Hence I suspected I hadn't understood the new settings possible when using the 7D's internal flash master function.
So it took a couple of weeks, where I had certain images heavily overexposed, until I started to wonder what was really going on, and thus tried to isolate the problem under more laboratory-like conditions.
Before that, I looked at the camera with a puzzled face when this happened, and tried for example to adjust the ISO, as I thought that maybe I had too much flash power available, too much for the flashes to adjust down to a level that gave proper exposure. That seemed to help, so for a while I thought that was the solution. Now I know that the simple reason that it helped was just because the flashes were firing at full throttle, and then of course ISO and/or aperture is the only way to control exposure.
You must also understand that since it's dependent upon if you bounce your slave flashes or not, and on which lens you use, as well as which focal length you set it too, it wasn't that easy to see the pattern in the beginning.

[windpig]

This is what I’m finding regarding over exposure using FEL with the on-board commander.
24-105 f4 and 100mm f2.8, same results, over exposure using FEL we’re talking major exposure issues.
I don’t think the on board flash commander can communicate nearly as well as a 580EX II in the hot shoe.
I was hopping the on board commander to be the same as 580EX II in the hot shoe, it isn’t.
Both lenses worked better in low light with AF assist when the 580EX II was in the hot shoe.
Ralph