Reasons to choose a7R IV
Released in 2019, a7R IV has about 850 mm² of sensor area, 61 MP effective resolution, and a 665 g body. Use these values to narrow the field, not as an overall image-quality score.
Side-by-side comparison
Sony a7R IV
vs Sony Alpha a9 II
VS
Sensor area
850 mm²
a7R IV847 mm²
Alpha a9 II- Area ratio
- 1:1
- Absolute difference
- 2 mm²
- Relative difference
- 0.3%
The a7R IV has the larger sensor area. More area usually means greater light-gathering potential, though real image quality still depends on sensor architecture and generation.
Key specification differences
a7R IVMetricAlpha a9 II
61 MPEffective pixels24.2 MP
35.7 × 23.8Sensor35.6 × 23.8
3.73 µmPixel pitch5.92 µm
13.93 µm²Pixel area35.01 µm²
7.18 MP/cm²Pixel density2.86 MP/cm²
1.01Crop factor1.01
3,840 × 2,160Maximum video3,840 × 2,160
665 gWeight678 g
SD/SDHC/SDXCStorageSD/SDHC/SDXC
NP-FZ100 lithium-ion battery Li-ion batteryBatteryNP-FZ100 lithium-ion battery Li-ion battery
Amber marks the value that is generally preferable in this comparison context. It is not an overall camera score.
How to choose between these cameras
The a7R IV has the larger sensor area. The a7R IV has the lighter body. The a7R IV has the higher effective resolution. The a7R IV and Alpha a9 II were both released in 2019. Also consider the lens system and subjects you shoot.
Reasons to choose Alpha a9 II
Released in 2019, Alpha a9 II has about 847 mm² of sensor area, 24.2 MP effective resolution, and a 678 g body. Use these values to narrow the field, not as an overall image-quality score.