Does anybody here encounter this problem? I just bought a 580ex II and I'm still learning. Every time I rotate the head of my flash to bounce the light off the wall or ceiling, the ETTL switch to TTL. Am I suppose to change some set up or something?

eTTL requires a preflash. That probably has something to do with it - but what camera are you using it with?

I noticed that sometimes on my 20d, but it wasn't constant. I now have a 30d and 40d, and never notice it.

I'm using the older version of 1Ds.
I just noticed that when I bring back the head of my flash to the original position, the TTL goes back to ETTL and it's not constantly happening.
Thank you for replying.

Jose