...Why is shooting in Tv with ETTL a bad thing when using the flash? What does having both the camera AND the flash in manual buy you - over say having just the flash in manual? Just trying to learn from everyone else.
1. Shooting in Tv with E-TTL will not let you control the aperture -> in case you need to control the DOF.
2. E-TTL is an evaluative system based on the AF points... depending on where the camera focuses -> you can end up with overexposure if the AF sensor lands on a dark spot, or underexposure if the AF sensor lands on a bright area. The 10D and dRebel do not take the distance information into consideration. http://www.stevesforums.com/forums/v...42&forum_id=37
3. Shooting with the camera on manual will let you control both the shutter and
the aperture while the flash is still on automatic E-TTL. The difference here is the exposure is not based on the AF points area anymore, but rather on a center-weight averaging -> more consistent exposure!
4. Shooting with both the camera and the flash on manual will allow you total control of the exposure -> you determine what it is and not the camera