Cosina CT-7

Jump to: navigation, search
This article is a stub. You can help by expanding it.

The Cosina CT-7 also known as Cosina Computer CT7 is a manual focus 35mm SLR from Cosina, announced in 1980.[1] It accepts K mount type lenses.

This camera was also sold as the Quantaray RZ 800 for the Ritz Camera shops in the North America, as well as the Petri GX-4.

It has an electromagnetic metal focal plane shutter with speeds from 8s to 1/1000 in automatic aperture priority mode, and 2s to 1/1000 with B in manual mode. Shutter speed is set by the up and down buttons on the shoulder area of the camera. Flash sync is at 1/100 a sec. The self-timer is electronic with a delay of approx 10 sec.

The CT-7 features a center-weighted, open-aperture TTL metering system with match-LED display (and over indicator). In manual mode the viewfinder's 11 shutter speed LED's aid in proper setting. A LT (Long Time) lamp is lit to signify a 2 to 8 sec. shutter speed in auto mode. The meter has a range of 2 to 19 EV at (ASA 100), and can be set for film speeds from 25 to 1600 ASA. The film transport uses a manual film advance lever and a rewind crank. A Cosina auto-winder accessory was also available for the camera. The CT-7 uses two 1.5v SR44 batteries.

A version of this camera designated the CT-7D (or Computer CT7D) was presented at the PMA 1981 show[2] and includes a non-removable date/data imprinting back.


  1. It was the flagship model listed in a slate of Cosina introductions in the April 1981 Popular Photography, pg. 222. Cosina began advertising in the May 1981 Popular Photography, pg.3 stating: "in North America, Cosina equipment has been sold only under other brand names. But now … Cosina is establishing its own name in the USA and Canada." (Scans via Google Books.)
  2. As reported in the July 1981 Popular Photography magazine, pg. 70 via Google Books.