Both Sony A7 and Leica SL have 24.0 MP resolution sensors but Sony A7's sensor is Full frame (35.8 x 23.9 mm ) and Leica SL's sensor is Full frame (36 x 24 mm ).
Since Leica SL'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 A7.
One other difference between these two cameras that is worth mentioning is that Leica SL's sensor doesn't have an anti-alias (Low-Pass) filter. Removing anti-alias filter increases the sharpness and level of detail but at the same time, it increases the chance of moiré occurring in certain scenes.
Below you can see the A7 and SL sensor size comparison.
Sony A7 and Leica SL have almost the same sensor size, so neither of them has any significant advantage over the other in terms of providing control over depth of field when used with the same focal length and aperture.
DxOMark Sensor Scores
Both Sony A7 and Leica SL 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 has scored 90, 2 points higher than SL.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Sony A7 |
90 |
24.8 bits |
14.2 Evs |
2248 ISO |
Leica SL |
88 |
25.0 bits |
13.4 Evs |
1821 ISO |