Both Nikon D810 and Pentax K-1 have Full frame sized 36.0 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 Pentax K-1 and Nikon D810 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 D810 and K-1 sensor size comparison.
Sensor Size and Resolution Comparison image of Nikon D810 and Pentax K-1 Cameras
Nikon D810 and Pentax K-1 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
Both Nikon D810 and Pentax K-1 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, D810 has scored 97, 1 points higher than K-1.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Nikon D810
97
25.7 bits
14.8 Evs
2853 ISO
Pentax K-1
96
25.4 bits
14.6 Evs
3280 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
Nikon D810
or the
Pentax K-1 ,
including hyperfocal distance.
