Olympus OM-1 was made in July 1972, it was after the Olympus Pen FT. The basic model of OM series continuing to even now. The model name was M-1 at the beginning though, it was changed OM-1 by name in next year because that the name of M-1 camera already existed in another camera manufacturer.|
As development of OM-1 was delayed a bit than other SLR, it's specifications were almost accomplished at its debut.
There a few different point other than a standard SLR. The shutter dial is mounted in outer ring of lens mount base, which is like leaf shutter. So did a Nikomat. It is better for the manual TTL camera in viewing proper exposures in the finder screen. A big dial on the top right, looks like shutter dial, is for setting ISO numbers of using film, can be set 25 to 1600 in 19 steps.
The mirror shock when shutter released is small in comparison with the other SLR. Its not clicky, not hard by using good air damper.
The OM-1 must be most among the compact SLR cameras in the world, which is only 750 grams even you attach the F1.4 50mm fastest lens. The lens looks bigger as the body is so small.
Olympus OM-1N was made in March 1979, it was almost 7
years past after the original OM-1 released. Olympus made already a model OM-2 in 1975 and it had a function of aperture preferred exposure system in the camera. The OM-1N, however, was nothing changed from the original except a small synchronized function improvement. Why they sold it as a brand new about 7 years later? I don't know but suppose they were thinking of many OM-1 users who supported with enthusiasm and stayed the price as original and with a particular about a manual SLR camera.
Being hold a popularity of manual focus SLR, the OM series cameras were kept to continue manufacturing. They are still making manual focus SLR like as OM-4, OM-3 Titan and OM 2000, even now.