canon G11 exposure issue
If the exposure compensation dial is confirmed to be set at zero (far left dial) then I would say that it sounds as if your G11 is malfunctioning and in need of repair or replacement.
I have two G11's and my prominent issues are that the rear control dial has stopped working on both cameras and they also suffer from dust/fibers behind front lens element. During nighttime photography any light shining into the lens lights up the schmutz like neon ruining the shot.
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