The Olympus OM-3 was released in 1983 and produced for only three short years until 1986. It was an update on the previous OM-1 and OM-2 cameras and continued those cameras' under-appreciated strive for excellence. If you were an Olympus fan then 1983 was a good year for you provided you had the budget to afford the new OM-3.
The design of the OM-3 remained pretty true to the OM-1. The OM-3 had its shutter speed ring located around the lens mount, keeping shutter, aperture and focus controls in one hand. But the OM-3 increased the top speed to 1/2000 all the while remaining a fully mechanical shutter that did not require batteries to fire. The same great Olympus OM viewfinder was in place: a bright and clear finder that somehow seems larger than should be possible for the compact camera it is housed in. Even the pull of the advance lever and the silky click of the shutter firing were consistent within the OM-3.
So what were the big improvements then? The most notable was the incredibly sophisticated metering system Olympus installed in the OM-3. Users had access to the standard center-weighted metering pattern just as they had previously, but in addition to that there were a spot, multi-spot, as well as highlight and shadow control modes. Spot metering was not a metering type commonly found in SLR cameras at this time, let alone a multi-spot mode that allowed the user to spot meter multiple areas of an image and have the meter average them. The shadow and highlight control modes were similar. The camera could spot meter a section of the image and told to meter in such a way as to render that spot white or black.
As mentioned, the OM-3 top shutter speed was increased to 1/2000. A hot shoe was also built into the camera. The OM-1 and OM-2 relied on a separate accessory that had to be screwed into the prism of the camera to supply a hot, so having one built into the OM-3 was certainly a convenience... and a feature found on almost every other SLR camera being made at the time.
To round out the OM-3 capabilities were interchangeable focusing screens, back doors (to add a Data Back for example) and motor drives (which allowed firing as fast as 5 fps in the right conditions). One notable omission from the OM-3 is any sort of auto exposure capability. This camera is manual all the way.
The OM-3 was discontinued in 1986, probably due in part to competition from the OM-1n and OM-4 cameras which were both in production at the same time. It's short production run and high market price combine to make this one of the rarer cameras in the entire OM series.