Pentax K-1 has a
36.0MP Full frame (35.9 x 24 mm ) sized CMOS sensor . On the other hand, Sony A65 has a
24.0MP APS-C (23.5 x 15.6 mm ) sized CMOS sensor and features Bionz processor.
Pentax K-1's sensor provides 12MP more than Sony A65'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.
Another difference between these two cameras is that Pentax K-1'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 K-1 and A65 sensor size comparison.
Sensor Size and Resolution Comparison image of Pentax K-1 and Sony A65 Cameras
As seen above, Pentax K-1 has a 2.4x Larger sensor area than Sony A65. 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.
DxOMark Sensor Scores
Both Pentax K-1 and Sony A65 sensors have been tested by DxoMark. DxoMark scores camera sensors for color depth (DXO Portrait), dynamic range (DXO Landscape) and low-light sensitivity (DXO Sports), and also gives them an overall score. Of the two cameras that we are comparing, K-1 has scored 96, 22 points higher than A65.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Pentax K-1
96
25.4 bits
14.6 Evs
3280 ISO
Sony A65
74
23.4 bits
12.6 Evs
717 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-1
or the
Sony A65 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(Full frame versus APS-C),
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.
