Both Canon T6i and Sony A77 have 24.0 MP resolution sensors but Canon T6i's sensor is APS-C (22.3 x 14.9 mm ) and Sony A77's sensor is APS-C (23.5 x 15.6 mm ).
Since Sony A77's has a larger sensor area with the same resolution, this means that it also has a larger pixel area hence better light collecting capacity for a given aperture compared to Canon T6i.
Below you can see the T6i and A77 sensor size comparison.
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 |