Reasons to choose GX-20
Released in 2008, GX-20 has about 365 mm² of sensor area, 14.6 MP effective resolution, and a 790 g body. Use these values to narrow the field, not as an overall image-quality score.
Side-by-side comparison
Samsung GX-20
vs Sony Alpha SLT-A55
VS
Sensor area
365 mm²
GX-20367 mm²
Alpha SLT-A55- Area ratio
- 1:1
- Absolute difference
- 2 mm²
- Relative difference
- 0.4%
The Alpha SLT-A55 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
GX-20MetricAlpha SLT-A55
14.6 MPEffective pixels16.2 MP
23.4 × 15.6Sensor23.5 × 15.6
5 µmPixel pitch4.76 µm
25 µm²Pixel area22.63 µm²
4 MP/cm²Pixel density4.42 MP/cm²
1.54Crop factor1.53
—Maximum video—
790 gWeight500 g
SDHC, Secure DigitalStorageSD/SDHC/SDXC/Memory Stick Pro Duo/ Pro-HG Duo
Lithium-Ion rechargeable (SLB-1137D) Li-ion batteryBatteryRechargeable NP-FW50 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 Alpha SLT-A55 has the larger sensor area. The Alpha SLT-A55 has the lighter body. The Alpha SLT-A55 has the higher effective resolution. The Alpha SLT-A55 is the newer release. Also consider the lens system and subjects you shoot.
Reasons to choose Alpha SLT-A55
Released in 2010, Alpha SLT-A55 has about 367 mm² of sensor area, 16.2 MP effective resolution, and a 500 g body. Use these values to narrow the field, not as an overall image-quality score.