Both Fujifilm X-H2 and Pentax 645D have 40.0 MP resolution sensors but Fujifilm X-H2's sensor is APS-C (23.5 x 15.6 mm ) and Pentax 645D's sensor is Medium format (44 x 33 mm ).
Since Pentax 645D'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 Fujifilm X-H2.
Another similarity between these two cameras is that both Pentax 645D and Fujifilm X-H2 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 X-H2 and 645D sensor size comparison.
Sensor Size and Resolution Comparison image of Fujifilm X-H2 and Pentax 645D Cameras
As seen above, Pentax 645D has a 4.0x Larger sensor area than Fujifilm X-H2. 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.
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
Fujifilm X-H2
or the
Pentax 645D ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(APS-C versus Medium format),
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.
