The SX-70 is a folding single lens reflex Land Camera first produced by the Polaroid Corporation in 1972.
It was the first instant SLR in history, and the first camera to use Polaroid’s new integral print film, which developed automatically without the need for intervention from the photographer. This was revolutionary at the time. The SX-70 has a folding body design, a 4-element 116mm f/8 glass lens, and an automatic exposure system. The camera allows manual focus as close as 10.4 inches (26.4cm), and has a shutter speed range from 1/175s to more than 10 seconds. A variety of models was offered, though all share the same basic design.
The SX-70 included many sophisticated design elements. A collapsible SLR required a complex light path for the viewfinder, with three mirrors (including one Fresnel reflector) of unusual, aspheric shapes set at odd angles to create an erect image on the film and an erect aerial image for the viewfinder. Many mechanical parts were precision plastic moldings. The body was glass-filled polysulfone, a very rigid plastic which could be plated with genuine copper-nickel-chromium. Models 2 & 3 used the less expensive and more-easily crackedABS in either Ebony or Ivory color. The film pack contained a flat, 6-volt “PolaPulse” battery to power the camera electronics, drive motor and flash. The original flash system, a disposable “Flash Bar” of 10 bulbs from General Electric, used logic circuits to detect and fire the next unused flash.