Both Sony A7 III and Sony A6300 have 24.0 MP resolution sensors but Sony A7 III's sensor is Full frame (35.8 x 23.8 mm ) and Sony A6300's sensor is APS-C (23.5 x 15.6 mm ).
Since Sony A7 III'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 Sony A6300.
Below you can see the A7 III and A6300 sensor size comparison.
As seen above, Sony A7 III has a 2.3x Larger sensor area than Sony A6300. 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 Sony A7 III and Sony A6300 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, A7 III has scored 96, 11 points higher than A6300.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Sony A7 III |
96 |
25.0 bits |
14.7 Evs |
3730 ISO |
Sony A6300 |
85 |
24.4 bits |
13.7 Evs |
1437 ISO |