Nikon D810 has a
36.0MP Full frame (35.9 x 24 mm ) sized CMOS sensor and features EXPEED 4 processor. On the other hand, Pentax 645D has a
40.0MP Medium format (44 x 33 mm ) sized CCD sensor and features Prime II processor.
Another similarity between these two cameras is that both Pentax 645D and Nikon D810 sensors lack anti-alias (Low-Pass) filters. 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 D810 and 645D sensor size comparison.
As seen above, Pentax 645D has a 1.7x Larger sensor area than Nikon D810. 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 D810 and Pentax 645D 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, D810 has scored 97, 15 points higher than 645D.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Nikon D810 |
97 |
25.7 bits |
14.8 Evs |
2853 ISO |
Pentax 645D |
82 |
24.6 bits |
12.6 Evs |
1262 ISO |