Canon 20D has a
8.0MP APS-C (22.5 x 15 mm ) sized CMOS sensor . On the other hand, Canon 50D has a
15.0MP APS-C (22.3 x 14.9 mm ) sized CMOS sensor and features Digic 4 processor.
Canon 50D's sensor provides 7MP more than Canon 20D'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 20D and 50D sensor size comparison.
Canon 20D and Canon 50D 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
DxOMark is a benchmark that scientifically assesses image quality of camera sensors. It 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. Canon 20D and Canon 50D sensors have been tested by DxO and the results show that 50D has a better overall score of 63, 1 points higher compared to 20D's score of 62.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Canon 20D |
62 |
21.9 bits |
11.0 Evs |
721 ISO |
Canon 50D |
63 |
21.8 bits |
11.4 Evs |
696 ISO |