Sony A7S has a 12.0MP Full frame (35.8 x 23.9 mm ) sized CMOS sensor and features Bionz X processor. On the other hand, Canon 5D MIII has a 22.0MP Full frame (36 x 24 mm ) sized CMOS sensor and features Digic 5+ processor.
Canon 5D MIII's sensor provides 10MP more than Sony A7S's sensor, which gives a significant advantage in real life. You can print your images larger or crop more freely.
On the other hand, please keep in mind that Max sensor resolution is not the only determinant of resolving power. Factors such as the optical elements, low pass filter, pixel size and sensor technology also affects the final resolution of the captured image.
Below you can see the A7S and 5D MIII sensor size comparison.
![Sony A7S vs Canon 5D MIII Sensor Size Comparison]()
Sensor Size and Resolution Comparison image of Sony A7S and Canon 5D MIII Cameras
Sony A7S and Canon 5D MIII have almost the same sensor size so none of them has any significant advantage over other in providing control over depth of field when used with same focal length and aperture.
DxOMark Sensor Scores
Both Sony A7S and Canon 5D MIII 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, A7S has scored 87, 6 points higher than 5D MIII.
| Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
|
Sony A7S |
87 |
23.9 bits |
13.2 Evs |
3702 ISO |
|
Canon 5D MIII |
81 |
24.0 bits |
11.7 Evs |
2293 ISO |