Sigma Quattro has a
29.0MP APS-C (23.5 x 15.6 mm ) sized CMOS (Foveon X3) sensor and features Dual TRUE III processor. On the other hand, Sony A6700 has a
26.0MP APS-C (23.5 x 15.6 mm ) sized BSI-CMOS sensor and features Bionz XR processor.
Another difference between these two cameras is that Sigma Quattro'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 Quattro and A6700 sensor size comparison.
Sensor Size and Resolution Comparison image of Sigma Quattro and Sony A6700 Cameras
Sigma Quattro and Sony A6700 have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture. On the other hand, since Sigma Quattro has 32% larger pixel area compared to Sony A6700, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.
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
Sigma Quattro
or the
Sony A6700 ,
including hyperfocal distance.
