I don't think that's quite right though I'm no expert so someone else can shoot me down! As above, in the unlocked position, tap on the screen and the yellow circle will appear where you've tapped and the exposure is set correctly for that circled area only............. if you them tap the little cross in the top corner of the circle, this will then set the whole picture up for an average exposure........ unfortunately, if you've got a very bright sky with dark ground below, the ground areas will then be too dark and difficult to see. The answer is to tap the screen on the dark ground areas so the exposure is set for that area only and looks good........ then tap the AE, the exposure for all the pictures will be locked on that setting and all the pictures should come out with the darker ground areas at the correct exposure (although the sky areas will probably be overexposed but that shouldn't really matter)