Both Canon T6i and Sony A77 have APS-C sized 24.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Below you can see the T6i and A77 sensor size comparison.
Sensor Size and Resolution Comparison image of Canon T6i and Sony A77 Cameras
As seen above, Sony A77 has a 1.1x Larger sensor area than Canon T6i. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.
DxOMark Sensor Scores
DxOMark is a benchmark that scientifically assesses image quality of camera sensors. It scores camera sensors for color depth (DXO Portrait), dynamic range (DXO Landscape) and low-light sensitivity (DXO Sports), and also gives them an overall score. Canon T6i and Sony A77 sensors have been tested by DxO and the results show that A77 has a better overall score of 78, 7 points higher compared to T6i's score of 71.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Canon T6i
71
22.7 bits
12.0 Evs
919 ISO
Sony A77
78
24.0 bits
13.2 Evs
801 ISO
Sensor size sets the circle of confusion, so it drives how much depth of field each
of these bodies gives you at a given aperture. You can calculate it exactly for the
Canon T6i
or the
Sony A77 ,
including hyperfocal distance.
