Both Canon 1D X II and Canon 70D have 20.0 MP resolution sensors but Canon 1D X II's sensor is Full frame (36 x 24 mm ) and Canon 70D's sensor is APS-C (22.5 x 15 mm ).
Since Canon 1D X II'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 70D.
Below you can see the 1D X MII and 70D sensor size comparison.
As seen above, Canon 1D X II has a 2.6x Larger sensor area than Canon 70D. 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 1D X II and Canon 70D 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, 1D X MII has scored 88, 20 points higher than 70D.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Canon 1D X II |
88 |
24.1 bits |
13.5 Evs |
3207 ISO |
Canon 70D |
68 |
22.5 bits |
11.6 Evs |
926 ISO |