I have been shooting in my backyard (dark), viewfinder blocked. For the same scene, I am getting three different shutter speeds (AV, ISO 1600, 5.6)
(1) Live View: 5 seconds
(2) Live View (OFF), LCD Light (OFF): 2.5 Seconds
(3) Live View (OFF), LCD Light (ON): 2 seconds
Now I understand the impact of LCD light (any news Canon!!), but why am I getting twice the shutter speed (slower) when using the live view?
Note: I have posted the same question in dpreview.com forum!