The Nikon AR-4 Double Cable Release is a specialized mechanical photography accessory engineered to provide automatic diaphragm control when using Nikon macro bellows systems (such as the PB-4, PB-5, or PB-6) with classic Nikon F-mount film cameras including the F, F2, FE, and FM series.
Key Functions & Mechanical Operation:
Simultaneous Dual-Triggering: It utilizes two independent mechanical cables connected to a single plunger. One cable triggers the camera's shutter, while the other connects to the bellows assembly or a BR-4 auto ring.
Aperture Sequencing: When the plunger is depressed, it stops the lens down to the preselected aperture split-seconds before firing the camera shutter. This allows you to compose and focus your macro shot with a bright, fully open view through the viewfinder.
Camera Compatibility: The camera-side connector utilizes the older Nikon-specific outer threads. It fits perfectly on the F, F2, FM, FE, and Nikkormat bodies, but will not natively fit newer camera models that use standard ISO-threaded shutter buttons.
Vibration Reduction: Mechanical isolation prevents hand movement from shaking the camera setup. Minimizing camera shake is vital in high-magnification macro photography where even minor vibrations blur the image.
