Olympus E-510 weighs 490 g (1.08 lb / 17.28 oz) and has external dimensions of 136 x 92 x 68 mm (5.35 x 3.62 x 2.68″). Considering that the average weight of DSLR type cameras is 774g, Olympus E-510 is a remarkably light camera for its class. With a thickness of 68mm, it has an average thickness for its class.
In order to give you a better idea about the real life size of Olympus E-510, we have added an image of how it looks next to a credit card and an AA type battery.
Now lets compare the weight and thickness of Olympus E-510 with its main competitors:
Olympus E-510 doesn't have any environmental sealings on its body so you got to be extra careful to protect it against water and dust. If you shoot under these conditions very often, consider checking Top DSLR Cameras with Weather Sealing page.