Reasons to choose EOS 40D
Released in 2007, EOS 40D has about 329 mm² of sensor area, 10.1 MP effective resolution, and a 822 g body. Use these values to narrow the field, not as an overall image-quality score.
Side-by-side comparison
Canon EOS 40D
vs Nikon D300s
VS
Sensor area
329 mm²
EOS 40D373 mm²
D300s- Area ratio
- 1.13:1
- Absolute difference
- 44 mm²
- Relative difference
- 13.5%
The D300s has the larger sensor area. More area usually means greater light-gathering potential, though real image quality still depends on sensor architecture and generation.
These cameras were released 2 years apart. Consider sensor generation when comparing pixel metrics.
Key specification differences
EOS 40DMetricD300s
10.1 MPEffective pixels12.3 MP
22.2 × 14.8Sensor23.6 × 15.8
5.7 µmPixel pitch5.51 µm
32.53 µm²Pixel area30.32 µm²
3.07 MP/cm²Pixel density3.3 MP/cm²
1.62Crop factor1.52
—Maximum video—
822 gWeight938 g
Compact Flash (Type I or II)StorageCompactFlash type I, CompactFlash type II, Microdrive, SDHC Secure Digital
Canon Lithium-Ion Li-ion batteryBatteryLithium-Ion EN-EL3e rechargeable 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 D300s has the larger sensor area. The EOS 40D has the lighter body. The D300s has the higher effective resolution. The D300s is the newer release. Also consider the lens system and subjects you shoot.
Reasons to choose D300s
Released in 2009, D300s has about 373 mm² of sensor area, 12.3 MP effective resolution, and a 938 g body. Use these values to narrow the field, not as an overall image-quality score.