Sony A6700 has a
26.0MP APS-C (23.5 x 15.6 mm ) sized BSI-CMOS sensor and features Bionz XR processor. On the other hand, Sony A57 has a
16.0MP APS-C (23.5 x 15.6 mm ) sized CMOS sensor .
Sony A6700's sensor provides 10MP more than Sony A57'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.
Below you can see the A6700 and A57 sensor size comparison.
Sensor Size and Resolution Comparison image of Sony A6700 and Sony A57 Cameras
Sony A6700 and Sony A57 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 Sony A57 has 62% larger pixel area (22.87µm 2 vs 14.10µm 2 ) compared to Sony A6700, it has larger pixel area to collect light hence potential to 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
Sony A6700
or the
Sony A57 ,
including hyperfocal distance.
