Both Canon SL2 and Sony A77 have 24.0 MP resolution sensors but Canon SL2'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 SL2.
Below you can see the SL2 and A77 sensor size comparison.
As seen above, Sony A77 has a 1.1x Larger sensor area than Canon SL2. 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
Both Canon SL2 and Sony A77 sensors have been tested by DxoMark. DxoMark 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. Of the two cameras that we are comparing, SL2 has scored 79, 1 points higher than A77.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Canon SL2 |
79 |
23.6 bits |
13.4 Evs |
1041 ISO |
Sony A77 |
78 |
24.0 bits |
13.2 Evs |
801 ISO |