Both Nikon D3 and Canon 450D have 12.0 MP resolution sensors but Nikon D3's sensor is Full frame (36 x 23.9 mm ) and Canon 450D's sensor is APS-C (22.2 x 14.8 mm ).
Since Nikon D3'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 450D.
Below you can see the D3 and 450D sensor size comparison.
As seen above, Nikon D3 has a 2.6x Larger sensor area than Canon 450D. 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 Nikon D3 and Canon 450D 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, D3 has scored 81, 20 points higher than 450D.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Nikon D3 |
81 |
23.5 bits |
12.2 Evs |
2290 ISO |
Canon 450D |
61 |
21.9 bits |
10.8 Evs |
692 ISO |