The Nikonos II, released in 1968, was an improved version of the original. Major changes included a switch from a rewind knob to a retractable crank for easier and quicker film rewinding, as well as the introduction of a hinged, pop-up film pressure plate for more convenient film loading. The camera retained the basic watertight, O-ring-sealed design and depth rating to 50 meters, as well as the same lens mount and shutter configuration as the Nikonos I. The viewfinder, shutter speeds, and overall internal layout were mostly unchanged, though the body shape was slightly streamlined. The addition of the “II” logotype next to the viewfinder marked this version. It weighed about 655g with lens, and offered improved handling, making it popular among both amateur and professional underwater photographers.