600ex-rt no E-TTL

[Ltdave]

popped the 600ex-rt on the 5d3 tonight for some indoor, on camera flash photography and all of a sudden, the speedlite wouldnt go into E-TTL. TTL, yes but that gave wildly overexposed images.

i popped the batteries out and then it went to E-TTL, but as soon as i took a photo, it went straight to TTL.

what gives? i cant change it to E-TTL with the mode button. it only will show TTL

 

[Dennis]

I think I had a similar experience once, and after not being able to fix it via button presses, etc., I just dismounted the Speedlite and re-fitted it making sure it was rammed in all the way home in the hotshoe, and the lock switch moved all the way to the right.

It worked!

I hope it is as simple as that, I assume that it thinks it has lost its brains when the connection is wonky, so it just fires on full output.

Dennis.

 

[paddler4]

If the flash hasn't gone bonkers, it sounds like it might be a bad connection. I had a (maybe?) related experience this week. I switched from a 5D IV to an R6 II, and I read that I would need an AD-E1 adapter to fit my 430 EX II to the new camera, so I bought one. Then someone posted that the adapter is unnecessary, so I removed it, and voila: the flash fired! It also overexposed very shot in E-TTL mode. I put the adapter back on and everything returned to normal.

The reason I mentioned this is that it seemed that the overexposure was probably a failure of communication between the flash and the camera. You don't need the adapter, but perhaps you are also getting a similar failure of communication.

I would also check to make sure all the contacts on the flash and shoe are clean.

 

[Ltdave]

If the flash hasn't gone bonkers, it sounds like it might be a bad connection. I had a (maybe?) related experience this week. I switched from a 5D IV to an R6 II, and I read that I would need an AD-E1 adapter to fit my 430 EX II to the new camera, so I bought one. Then someone posted that the adapter is unnecessary, so I removed it, and voila: the flash fired! It also overexposed very shot in E-TTL mode. I put the adapter back on and everything returned to normal.

The reason I mentioned this is that it seemed that the overexposure was probably a failure of communication between the flash and the camera. You don't need the adapter, but perhaps you are also getting a similar failure of communication.

I would also check to make sure all the contacts on the flash and shoe are clean.

ive used this same flash unit on this same 5d3 for 8 years? no need for any adapter.

i removed the speedlite from the body, pulled the batteries, hit the 'reset' buttons and remounted and powered it up. i can get E-TTL but as soon as i hit the shutter button or BBF (as ive done for nearly a decade) it automatically changes to TTL.

i put batteries in another 600ex-rt, mounted it on the camera, turned it on and it went to E-TTL, and stayed there for several test shots.

CAVEAT: the rubber boot around the shoe on the speedlite, came off and was lost a couple of weeks (months?) ago but everything looks clean regardless

 

[Wilt]

Have you tried to run a pencil eraser across the contacts in the hotfoot of the problem 600RT? The fact that your other 600RT seems to have no issues points to issues in the communications between flash and camera which permits the flash unit to detect it is mounted on an eTTL compatible body.

 

[Wilt]

The reason I mentioned this is that it seemed that the overexposure was probably a failure of communication between the flash and the camera. You don't need the adapter, but perhaps you are also getting a similar failure of communication.

I would also check to make sure all the contacts on the flash and shoe are clean.

Yes, flakey connection from flash to camera means that the camera command to flash at a predetermined fractional output level has failed, causing the flash to fire at full power instead.

 

[paddler4]

I wasn’t suggesting you need an adapter. I used that experience to show that a flaky connection can produce exactly the symptoms you are having. That’s why I suggested cleaning the contacts.

 

[ImageMaker]

Sometimes remove all batteries and replace with fresh.