Pentax K-S1 has a
20.0MP APS-C (23.5 x 15.6 mm ) sized CMOS sensor and features Prime MII processor. On the other hand, Nikon D5300 has a
24.0MP APS-C (23.5 x 15.6 mm ) sized CMOS sensor and features Expeed 4 processor.
Another similarity between these two cameras is that both Nikon D5300 and Pentax K-S1 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-S1 and D5300 sensor size comparison.
Pentax K-S1 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. On the other hand, since Pentax K-S1 has 20% larger pixel area compared to Nikon D5300, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.
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-S1 and Nikon D5300 sensors have been tested by DxO and the results show that D5300 has a better overall score of 83, 5 points higher compared to K-S1's score of 78.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Pentax K-S1 |
78 |
23.5 bits |
13.0 Evs |
1061 ISO |
Nikon D5300 |
83 |
24.0 bits |
13.9 Evs |
1338 ISO |