Both Pentax K-3 II and Nikon D5300 have APS-C sized 24.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Another similarity between these two cameras is that both Nikon D5300 and Pentax K-3 II sensors lack anti-alias (Low-Pass) filters. 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-3 II and D5300 sensor size comparison.
Sensor Size and Resolution Comparison image of Pentax K-3 II and Nikon D5300 Cameras
Pentax K-3 II and Nikon D5300 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.
DxOMark Sensor Scores
DxOMark is a benchmark that scientifically assesses image quality of camera sensors. It 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. Pentax K-3 II and Nikon D5300 sensors have been tested by DxO and the results show that D5300 has a better overall score of 83, 3 points higher compared to K-3 II's score of 80.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Pentax K-3 II
80
23.6 bits
13.6 Evs
1106 ISO
Nikon D5300
83
24.0 bits
13.9 Evs
1338 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-3 II
or the
Nikon D5300 ,
including hyperfocal distance.
