600EX RT overexposing in ETTL

[rcarvillephoto]

I am using a 5dMKiii with a 600 EX RT and a wizard connected via the sync port on the camera body.   (Wizard fires the room strobes I set up to as fill light for the entire room. 

While shooting events I the 600 is overexposing majorly and randomly.  I have had to knock the EV on the flash all the way down to -3 and occasionally it even overexposes on that setting.  I can't use manual mode on the flash as I am in a variety or distances and lighting situations.  

HELP!  I have searched the internet high and low and the only thing I foudn was that on ETTL the flash only meters via the center weight point.  So for example I focus on the eyes then recompose.  When I recompose the center weight moves to a black jacket.  So instead of exposing for the face it goes for the black jacket.  This makes sense to me.  My question is how do I change that to say lock the meter when focusing?

Thanks in advance!

Ryan

[TCampbell]

Can you put the 600EX into manual mode, dial the power level down and make sure that it actually does fire using limited power?

There was once a known issue with 580EX II units in which they always wanted to fire at full power regardless of the selected power level (if a unit developed that issue, it would require sending in for service.)

I've not heard of a 600 doing this, but you may want to test that it isn't just firing at full power all the time.  

[Skirball]

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@TCampbell wrote:

Can you put the 600EX into manual mode, dial the power level down and make sure that it actually does fire using limited power?

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He stated earlier that doesn't want to do that since he's walking around taking candids at various distances.

That said, if you have no other option it can work.  You just have to keep relatively consistent distances.  The variance would likely be less than the over exposure you're dealing with now.  Just treat it as a prime flash  🙂

[TCampbell]

I should have been more clear... I meant to "test" that you can force the flash to dial back the power -- not meant to imply that this is how you should use it. The 580EX II had an issue with PocketWizards whereby it would blow some resister and from then on it would only fire at full power no matter what you do. So I was really suggesting the test as a way to confirm this has not happened to the 600EX RT.

[HANYRAMGt]

In the camera settings>>External speedlite Control>>Flash Function Settings>>Flash exposure Compensation>>0

[RobertTheFat]

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@HANYRAMGt wrote:
In the camera settings>>External speedlite Control>>Flash Function Settings>>Flash exposure Compensation>>0

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You're the first person to post to this thread in almost six years. Not quite a record, but close.

And yes, the site should not display the posting date so faintly.

[HANYRAMGt]

I had this problem, searched for a solution, did not find the solution, then figured it out, and I thought to share it.