Pentax K-500 has a
16.0MP APS-C (23.7 x 15.7 mm ) sized CMOS sensor and features PRIME M processor. On the other hand, Sony A68 has a
24.0MP APS-C (23.5 x 15.6 mm ) sized CMOS sensor and features Bionz X processor.
Sony A68's sensor provides 8MP more than Pentax K-500'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 K-500 and A68 sensor size comparison.
Sensor Size and Resolution Comparison image of Pentax K-500 and Sony A68 Cameras
Pentax K-500 and Sony A68 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.
DxOMark Sensor Scores
At Camera Decision, we also look at Dxo Mark sensors when available as we think it is a good indicator of image quality.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Pentax K-500
79
23.7 bits
13.1 Evs
1087 ISO
Sony A68
79
24.1 bits
13.5 Evs
701 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
Pentax K-500
or the
Sony A68 ,
including hyperfocal distance.
