Originally posted by Tom M that just seem retarded to me if there's no way to stop that.. There should be a way to completely control the unit from the camera - period!
Interesting reaction, Tom. I also thought it was very queer at first, but what I felt was that the flash should be controlled entirely from the 540's control panel, which after all is easier to get to than the Fn menu.
But now that I've gotten over my surprise, I've decided it's not a BAD thing after all. So long as you know how it works, you can make it work for you rather nicely. For example, say you're shooting wirelessly and the flash is on a flash stand 10 ft away, while you're at the camera which is mounted on a tripod. Rather than hike over to the 540 to dial up the flash, you can do it from the camera. And of course, if the camera's setting is at +/-0 FEC, then you can control the flash normally from the dial on the back of the 540. Finally, I have complained in the past that the 540 can't go to +2, and I will also confess that I was mostly voicing complaints I heard from others. Well, I think now that's not quite correct. If I dial the 540 to +1 and do the same thing in the camera, I get more flash output than I do otherwise. So apparently it is possible to get +2 FEC. You just have to do it by combining these adjustments.
For the most part, I think the key lesson here is, if you're not getting the exposure you expect while using a 540 FGZ, check the camera's flash exposure compensation setting in the Fn menu. That's what led me to this little personal discovery. I was doing some tests and kept getting darker exposures than I expected and it took me fifteen minutes of playing around before I noticed that the Fn menu's FEC was dialed down to -2.
What I don't understand is, how does this affect the output from TWO flashes? I've been testing wireless using the on-camera flash only as a trigger/controller. But when I go into the custom menu and change the setting for flash output in wireless mode to On (so the camera's built-in flash contributes its light to the picture), it seems to me that the result is STILL additive. This is a bit harder for me to test, at least I have a harder time figuring out how to detect the relative contribution of the two flashes. I've put the off-camera flash off to the side and throwing its light very clearly in a direction different from the on-camera flash, which is throwing its light straight forward. As far as I can tell, changes to the on-camera FEC affect the output from BOTH light sources. When I dial the Fn menu's FEC down to -2, not only does the light on the front of the subject get diminished, the light from the side (coming from the 540FGZ) is diminished, also. THIS makes my head hurt at the moment and I'm not going to bother getting the other 540 out and trying THREE flashes until I've had a chance to get a good night's rest.
Will
Will