580EXT II switches from ETTL TO TTL?

I was shooting a wedding the other evening, using a 580EXII on my MKIII and using the Stophen diffuser. I don't shoot weddings and I've used an on camera flash maybe a dozen times but this was last minute casual wedding and family like friends. It came out really well, indoors and outdoors shooting but...

I chimped a lot because I was unsure about the flash and quite frankly I was getting very pleased by the results considering- with the exception of some of the color balance.

But for some reason about three or four times it switched from ETTL to TTL and blew out the exposures! I'd turn it off and go through the Mode switch etc and it would find ETTL actually not sure what did it, I was just clicking things fast.

Why or what did I do while shooting that caused this, could I be bumping
Something?

Also I have no intention of shooting a wedding again- I hope, but I am intrigued by what I could do with an on camera flash- but don't tell anyone kay!

Jannie wrote in post #12849790
I was shooting a wedding the other evening, using a 580EXII on my MKIII and using the Stophen diffuser. I don't shoot weddings and I've used an on camera flash maybe a dozen times but this was last minute casual wedding and family like friends. It came out really well, indoors and outdoors shooting but...

I chimped a lot because I was unsure about the flash and quite frankly I was getting very pleased by the results considering- with the exception of some of the color balance.

But for some reason about three or four times it switched from ETTL to TTL and blew out the exposures! I'd turn it off and go through the Mode switch etc and it would find ETTL actually not sure what did it, I was just clicking things fast.

Why or what did I do while shooting that caused this, could I be bumping
Something?

Also I have no intention of shooting a wedding again- I hope, but I am intrigued by what I could do with an on camera flash- but don't tell anyone kay!

The most likely reason for that happening is the flash loosing connection with camera. This can happen if the flash is not tightened down in the hot shoe. If you were using an off-camera cable, it could be loose on either end (or maybe a break in one of the wires in the cable).

I've also seen this happen when the hotshoe had started to separate from the body due to loose screw(s) used to keep the hotshoe attached to the body.

I had to release the lever that tightens the flash onto the hot shoe but it did switch to TTL I wonder if I hadn't tightened the lever enough- thanks

Its a very common problem on the canon 580ex2 and check the following article for a diy fix:

http://shimworld.wordp​ress.com …ite-580ex-ii-hotshoe-fix/

God, I love this forum.

Thanks kenwood33

Canon knows about the contact issuses and has re-designed the contacts points from "rounded" to "pointy".

https://photography-on-the.net …p?p=12697656&po​stcount=23

No way I am opening that up. Darn!

Where are you located? Just order a new foot from Canon. I ordered one and it was less than $50. You could then take it to a local camera repair store and have them change it. Perhaps you know someone who is handy with this sort if stuff. 4 screws and one plug to change it. It took less than 15 minutes. No springs or anything like that when just exchanging the foot.

The camera hot shoe mount was re-designed on newer Canon cameras to fit the 580EX II's weather sealing. I wonder if part of the problem is the rubber boot that forms the seal. Maybe it doesn't fit the older cameras well.

I don't think the rubber boot is an issue because this problem occurs on my 7d (as well as on the 40d and xsi).

What's weird about everything people are saying here is that I've NEVER had a problem with this issue until I read a couple of weeks ago about someone else with this problem, but he was using a Canon 5DMII with a Canon 550EX Speedlite and was wondering if it was that the Speedlite was an older model. Of course I assured him that it was not because I have a Canon 5DMII as well as the 5DMI and I own 6 Canon 550EX Speedlites and they work FLAWLESSLY on both of my Camera Bodies..... until I read his post and my very next wedding, this exact thing started happening using my 5DMII, it goes from E-TTL Mode to TTL and blows out the shots. Of course, you can immediately tell that something is wrong because you can feel that the flash is firing FULL power. However when I switched the same Speedlite to the 5DMI..... NO PROBLEMS! Switched back to the 5DMII, happened again! So I changed out 2 other flashes and still the same incident..... So, I just shot the rest of the wedding on the 5DMI.
Now let's fast forward to this past weekend. I just so happened to pick up a MINT Canon 580EXII for little of nothing and used on another wedding with the 5DMII and sure enough a couple of hours into the wedding it goes into TTL Mode. I switched it off, pulled it off the body then put it back on again. It goes back into E-TTL Mode and I didn't have a problem with it again for the rest of the day.....

JUST WEIRD.....

http://www.uscamera.co​m/cy2-4220.htm