Nikon F Photomic TN designed was introduced in 1967 (discontinued 1968). The Nikon F Photomic TN is one of Nikon's system-oriented manual SLR cameras with interchangeable viewfinders, focusing screens, and comprehensive motor drive capability. The center-weighted exposure measurement was added to the Photomic finder. Sixty percent of the exposure is read on a 12mm circle in the center of the viewfinder. It is identified by the letter "N" inscribed on the finder over the on/off switch. It has prong for wide-open metering.