Titus213 wrote in post #5809107
I'm actually not sure if you got it....
It allows you to point at something other than the center of the scene to get the flash measurement.
Hmm. I think i did get it, or then i am still not getting it.
I understand this so, that you must point the center focus point to your subject and then press * to get it to "remember" that flash exposure from the subject and after this i can lock focus, recompose and take pic.
When i don't press * button the E-TTL is not measuring the flash exposure from the subject, assuming that i have recomposed after locking focus, instead it's measuring from where ever i am pointing the camera after the re-compose?
I tested this with my 40D's own flash. When i didn't use the * button it overexposed the target a little compared to the shot that was taken with the * button. My "target" was quite close and if i didn't lock the flash before taking the pic it seemed like it tried to get the backround ( which was in the center after re-composing ) to be exposed correctly and not the target which was the point of focus. So it ended up overexposing the front of the image where the target was.
I think i do get it.. damned if i don't.
The first is taken with * button, and the other is taken without. The brown jacket was the target ( sorry, didn't feel like off the couch for the tes ) . Not a big difference, but expected one..
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