The next Nikon model, the F3 adopted the horizontal-traveling method, with one glaring difference --- electronic control of the shutter.
First, the leading operating unit (called the "control unit") produces a timer start signal to ensure that the front curtain and timer circuit start accurately.
The front curtain then begins traveling. The rear curtain, which is pulled up by magnet, starts its movement after a delay set by the timer.
One of the most important features of the F3 was the discontinuation of the rear-curtain shoe unit that could be found in every Nikon model dating back to the "I".
As can be seen in the diagram of each shutter unit for conventional models including the F, the rear-curtain hook stops the rear-curtain shoe unit which is coupled to the rear-curtain drum (a thick drum enveloped by a curtain).
Put another way, the rear-curtain hook indirectly stops the drum. On the other hand, with the F3, the rear-curtain hook directly stops and releases the rear curtain.
This method offered greatly reduced friction in the rotation of the shutter shaft, as well as in the release time lag.
For smoother operation, four ball bearings are used --- one for the control unit shaft, two for the front-curtain shaft and the last one between the front-curtain shaft and rear curtain. This was a significant change, as conventional models had used only one ball bearing.
A new brake system was also introduced, in which the brake drum was pressed by a brake shoe.
For the first time since the Nikon"I", Nippon Kogaku reviewed the length of the shutter ribbon and the dimensions of the shutter curtain for the F3.
The thinner ribbons and smaller curtains contributed to an overall reduction in the size of the camera.
By the way, since the Nikon F, the camera's X-contact had been overworked. With the F3, the X-contact is fixed by only one screw, and can easily be replaced.
Although the use of a Nikon Speedlight does not damage the X-contact, damage can be caused by certain professional-use flash units that operate at high voltages.
We could go on about the technical features of the F3's shutter forever.
It was developed with the goal being to make a horizontal-traveling shutter that was perfect in all respects.
With the F3, however, Nippon Kogaku was not able to create a "high-speed shutter" that enabled Speedlight synchronization at 1 / 250 sec.
After that, they went to work on a "vertical-traveling shutter" for Nikon one-figure F-series models.