The Sigma SD1 is 23.5 mm wider, 44.4 mm taller, 45.7 mm deeper and 381 g heavier than the Olympus PEN E-P3.
| Olympus PEN E-P3 | Sigma SD1 | |
|---|---|---|
| Size (W × H × D) | 122 × 69.1 × 34.3 mm | 145.5 × 113.5 × 80 mm |
| Weight | 369 g | 750 g |
| Lens | Micro Four Thirds | Sigma SA |
| Sensor | Four Thirds | — |
| Announced | 2011 | 2010 |