Nikon Z7 has a
46.0MP Full frame (35.9 x 23.9 mm ) sized BSI-CMOS sensor and features Expeed 6 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.
Nikon Z7's sensor provides 6MP more than Pentax 645D'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.
Another similarity between these two cameras is that both Pentax 645D and Nikon Z7 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 Z7 and 645D sensor size comparison.
As seen above, Pentax 645D has a 1.7x Larger sensor area than Nikon Z7. 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 Z7 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, Z7 has scored 99, 17 points higher than 645D.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Nikon Z7 |
99 |
26.3 bits |
14.6 Evs |
2668 ISO |
Pentax 645D |
82 |
24.6 bits |
12.6 Evs |
1262 ISO |