Nikon Nikonos IV-A
The Nikonos IV-A, introduced in 1980, was an advanced underwater camera that added aperture-priority automatic exposure to the Nikonos system for simplified underwater photography. This specialized 35mm camera maintained waterproof construction rated to 50 meters (160 feet) while incorporating sophisticated automatic exposure capabilities that made underwater photography more accessible to recreational divers. The IV-A featured bright optical viewfinder, improved TTL metering, and compatibility with the full range of UW-Nikkor underwater lenses. Key innovations included aperture-priority automation, enhanced exposure control, and refined ergonomics for easier underwater operation. The camera was designed for both serious underwater photographers and recreational divers who wanted professional-quality results without complex manual exposure calculations. The Nikonos IV-A successfully democratized underwater photography by making advanced exposure control automatic, allowing photographers to concentrate on composition and timing rather than technical settings, while maintaining the reliability and image quality expected from the Nikonos series.
Files
Service manual for the Nikon Nikonos IV-A