Metering
Like the sensor found in the previous SLT cameras, the Alpha 77 makes use of a 1,200-zone evaluative metering system, collecting information in either multi-segment, spot or centreweighted areas.
A useful test to understand the behaviour of an evaluative multi-segment mode in a metering system is capturing the same scene but adjusting the level of brighter and darker areas in the frame. By angling the camera upwards in a landscape and increasing the amount of sky in the frame, the Alpha 77 could underexpose a little sooner for my liking, as skies can be a little bright even in a 50/50 split in the frame.
However, I largely kept metering to the multi-segment setting. Spot metering is limited to the active AF points, which varies according to the AF area selected. In local AF area, any one of the 19 points can be selected, while in zone AF it is one of the three central AF points from each of the three zones. All these points are in the centre portion of the frame, which limits where the spot reading is taken. I found a quicker method for an accurate exposure is keeping peaking activated to indicate blown-out highlights and adjust settings accordingly through exposure compensation.
