This camera is often referred as a representative of light-weight small SLR, but the real intention of this camera was to be "system camera" with more than 280 numbers of accessories and lenses, for photography in whole area "from space to bacteria".
For making it possible to use the camera body with every type of optical equipment, lens mount with large diameter and large size mirror were firstly designed and fixed.
Then the body was designed based on human-engineering. Body size was decided after collecting thousands of size data of world-wide human hand shapes of gripping object. It would have been technically possible to design this camera in smaller size than it finally is, but Olympus did not do that. Olympus selected ideal body size to hold and use based on their research.
While they made great effort in shortening the height of the body to achieve their ideal body size, they adopted normal size advance lever and large size rewind crank lever to produce comfortable usability.
This outstanding SLR in 1970s still keeps mass of enthusiastic users over the world.



Manual meter with needle centering operation has rapid response and is convenient to use.

[Not very good]

Rotation angle of film advance lever is larger than that of OM-3/OM-4.
To turn on exposure meter, a small switch other than shutter button needs to be operated each time, while OM-3/OM-4 meter can be turn on when only shutter button is halfway pressed (and the meter is automatically turned off after certain seconds).
In this aspect OM-3/OM-4 spec for usage is more sophisticated in my opinion, but this does not make any sense to OM-1 enthusiasts who perfectly get used to operate OM-1.

Shutter sound(.wav)
OM-1N Japan model body
If you are a OM camera collector and are interested in OM-1NEW Japan model withOUT [MD] logo plate, please check.

Mechanical shutter, manual metering.
Start of sales : 1973
Weight Body : 510g + 50mmf1.8 : 165g =675g