Adventurous unprecedented experiments were carried out in developing the Nikon EM.
With the success of Nikomat (Nikkormart), Nippon Kogaku K.K. gained confidence developing general-use models, and pushed cost reduction and mass production to broaden its market and market share.
The initial idea that the camera was to be based on Nikon FM (1977, see part 9.) body was reconsidered, starting with basic camera mechanisms.
Take the film winding mechanism. Here, the goal was to minimize the number of gears, making it from scratch by studying past cameras, among other things.
The company concluded that the winding lever should be positioned between the winding spool and the sprocket (See fig. on the left).
This, however, provided insufficient space for the winding lever reserve joint, so a special mid-folding winding lever was devised.
A unique feature of this winding mechanism is that it can wind bit by bit, even though it is a square-type focal plane shutter camera. With conventional square-type shutters, a big lever on the camera bottom moves sideways, and the shutter and mirror mechanism are charged by repetitive sideways movement.
This lever is directly connected to the winding axle with a crank, so the winding lever axle also needs to be moved repetitively, making fractional winding impossible.
However, in the EM, the rotation of film winding axle is done by the cam and roller's repetitive straight movement, making winding fractional.
About the reason why the EM incorporated this mechanism at great risk of making the entire mechanism complicated, which even the upper-class Nikon FM and FE (1978, see part 10.) models did not feature, the designer in charge of this mechanism at that time flatly said : "I don't like cameras that cannot wind fractionally !".
Evidently, those were good old days when designer's personal liking might be reflected upon the product in a good way.