Sony A7 IV has a
33.0MP Full frame (35.8 x 23.8 mm ) sized BSI-CMOS sensor and features Bionz XR processor. On the other hand, Sony RX1R II has a
42.0MP Full frame (35.9 x 24 mm ) sized BSI-CMOS sensor and features BIONZ X processor.
Sony RX1R II's sensor provides 9MP more than Sony A7 IV'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 similarity between these two cameras is that both Sony RX1R II and Sony A7 IV 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 A7 IV and RX1R II sensor size comparison.
Sensor Size and Resolution Comparison image of Sony A7 IV and Sony RX1R II Cameras
Sony A7 IV and Sony RX1R II 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
Sony A7 IV
97
25.4 bits
14.7 Evs
3379 ISO
Sony RX1R II
97
25.8 bits
13.9 Evs
3204 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
Sony A7 IV
or the
Sony RX1R II ,
including hyperfocal distance.
