Both Leica M9 and Canon M have 18.0 MP resolution sensors but Leica M9's sensor is Full frame (36 x 24 mm ) and Canon M's sensor is APS-C (22.3 x 14.9 mm ).
Since Leica M9'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 M.
Another difference between these two cameras is that Leica M9'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 M9 and M sensor size comparison.
Sensor Size and Resolution Comparison image of Leica M9 and Canon M Cameras
As seen above, Leica M9 has a 2.6x Larger sensor area than Canon M. 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 Leica M9 and Canon M 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, M9 has scored 69, 4 points higher than M.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Leica M9
69
22.5 bits
11.7 Evs
884 ISO
Canon M
65
22.1 bits
11.2 Evs
827 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
Leica M9
or the
Canon M ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(Full frame versus APS-C),
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.
