The Olympus E-620 is 26 mm narrower, 23 mm shorter, 59 mm thinner and 959 g lighter than the Pentax 645D.
| Pentax 645D | Olympus E-620 | |
|---|---|---|
| Size (W × H × D) | 156 × 117 × 119 mm | 130 × 94 × 60 mm |
| Weight | 1,480 g | 521 g |
| Lens | — | Four Thirds |
| Sensor | — | Four Thirds |
| Announced | 2010 | 2009 |