Canon 70D has a
20.0MP APS-C (22.5 x 15 mm ) sized CMOS sensor and features Digic 5+ processor. On the other hand, Canon 30D has a
8.0MP APS-C (22.5 x 15 mm ) sized CMOS sensor .
Canon 70D's sensor provides 12MP more than Canon 30D'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 70D and 30D sensor size comparison.
Canon 70D and Canon 30D have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture. On the other hand, since Canon 30D has 143% larger pixel area (41.21µm2 vs 16.91µm2) compared to Canon 70D, it has larger pixel area to collect light hence potential to have less noise in low light / High ISO images.
DxOMark Sensor Scores
Both Canon 70D and Canon 30D 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, 70D has scored 68, 9 points higher than 30D.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Canon 70D |
68 |
22.5 bits |
11.6 Evs |
926 ISO |
Canon 30D |
59 |
21.5 bits |
10.8 Evs |
736 ISO |