Pentax 645D has a
40.0MP Medium format (44 x 33 mm ) sized CCD sensor and features Prime II processor. On the other hand, Leica M10 has a
24.0MP Full frame (35.8 x 23.9 mm ) sized CMOS sensor and features Maestro II processor.
Pentax 645D's sensor provides 16MP more than Leica M10'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 difference between these two cameras is that Pentax 645D's sensor lacks anti-alias (Low-Pass) filter. 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 645D and M10 sensor size comparison.
Sensor Size and Resolution Comparison image of Pentax 645D and Leica M10 Cameras
As seen above, Pentax 645D has a 1.7x Larger sensor area than Leica M10. 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
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. Pentax 645D and Leica M10 sensors have been tested by DxO and the results show that M10 has a better overall score of 86, 4 points higher compared to 645D's score of 82.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Pentax 645D
82
24.6 bits
12.6 Evs
1262 ISO
Leica M10
86
24.4 bits
13.3 Evs
2133 ISO
Sensor size sets the circle of confusion, so it drives how much depth of field each
of these bodies gives you at a given aperture. You can calculate it exactly for the
Pentax 645D
or the
Leica M10 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(Medium format versus Full frame),
so compare them at the same framing rather than the same focal length.
Put the same focal length on the smaller sensor and it will show less depth of
field, not more, because it also crops tighter. The calculator shows the
full frame equivalent focal length for each body so you can match the framing.
