battery drain problem with canon 600ex flash

[janbracciale]

I am new to Canon and bought a 5d mk III with the 600ex flash.   I have professional friends who have helped me with my change in brands.  I used the flash with new eneloop rechargeable batteries in the flash and also attached to a charger pack for a concert  event.  I needed to take 2 consecutive shots of each group of people in a reception line which lasted about 2 hours.  During approximately tThe last 1/2 hour the flash sync time slowed considerably to the point that I had to wait for the second shot.  I also cannot use a Gary Fong lightsphere on this flash -  results are an underexposed orange/yellow image.  I tested this flash vs. my friends 5dII with the 580 at exact camera and flash settings, the 580 was fine with the lightsphere. Has anyone had this experience?  I am wondering if this flash is defective? 

[jfo]

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@janbracciale wrote:

... reception line which lasted about 2 hours.  During approximately tThe last 1/2 hour the flash sync time slowed considerably to the point that I had to wait for the second shot...

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Not sure about the Gary Fong issue, but regarding re-cycle time, it sounds like your batteries just ran low. 

[p4pictures]

I think you may have run the batteries flat.

The colour issue might be that the flash tries to read the white balance from a filter fitted to the flash head. There's a little sensor on the bottom side of the flash head for this. It could be that the flash was reading the lightsphere and sending colour information to the camera body. Try changing P.Fn 05 on the flash to 1: OFF instead of 0: AUTO and see if this fixes things. Also the colour of the gary fong (or clones) might be the issue, it could be colouring the light for you. In this case a check with a grey card and then manual white balance would be helpful. You could do this before the folks arrive and then it would be pretty good for the whole event.

I tend to use speed straps to fit gels, grids and other modifiers to my flashes so I have turned this automatic filter detection feature off on all my 600EX-RTs.

Brian