Leica X-U has a
16.0MP APS-C (23.6 x 15.7 mm ) sized CMOS sensor . On the other hand, Fujifilm X100 has a
12.0MP APS-C (23.6 x 15.8 mm ) sized CMOS sensor and features EXR processor.
One other difference between these two cameras that is worth mentioning is that Fujifilm X100's sensor doesn't have an 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 X-U and X100 sensor size comparison.
Sensor Size and Resolution Comparison image of Leica X-U and Fujifilm X100 Cameras
Leica X-U and Fujifilm X100 have almost the same sensor size, so neither of them has any significant advantage over the other in terms of providing control over depth of field when used with the 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
Leica X-U
or the
Fujifilm X100 ,
including hyperfocal distance.
