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View Full Version : Blinking 4.0 to Blinking 29 Just by Turning On Flash


dphoto
26th of September 2004 (Sun), 16:13
Hey everyone,

Something's happening that I just don't understand. I turn on my Digital Rebel with kit lens in Tv mode at 1/200. The aperature value shows a blinking 4.0. This I understand; it means there is not enough light and the shot will be underexposed.

Then I turned on my 550 EX. If I use ETTL mode, the camera sticks with the blinking 4.0. This is what *should* happen since the flash (as far as I understand the universe) has no affect on the camera's decision to choose an aperature. That's fine. But if I switch the flash to manual mode (1/16 power), then the camera starts blinking 29 for aperature value. Why?

First of all, the flash is not supposed to factor into the decision. Second of all, wouldn't a blinking 29 indicate that the shot is going to be overexposed? Well, that certainly wasn't the case. I took the shot just for the heck of it, and it was underexposed by 2 stops.

Can anyone help with this? It doesn't make any sense to me. This doesn't happen in Av or M mode. I just tried P mode, and it causes a blinking 29 as well.

Thanks for any help with this!
-Deva