The Nikonos I was introduced in 1963 as the first underwater camera in Nikon’s legendary Nikonos series, based on the design of the Calypso-Phot. Built to be fully watertight to depths of 200 feet (60 meters), it featured a rugged body with O-ring seals, a bayonet-mount lens system, and simplified controls designed for use while diving. Compatible with high-quality lenses from French manufacturers, the Nikonos I combined durability with precision, allowing photographers to capture sharp, vibrant images underwater. Its release marked the beginning of a long line of Nikonos cameras, which became a cornerstone in the evolution of underwater photography, setting standards for performance, reliability, and ease of use.