The Pentax 6X7, Pentax 67 and Pentax 67II, are medium format SLR camera system introduced in 1969 with the original Pentax 6X7 and discontinued in 2009 with the Pentax 67II. It produces 55×70 mm images on 120 or 220 roll film. The system consist of the camera bodies, an interchangeable prism viewfinders, lenses and variety of accessories. An classic Pentax 6X7 outfit typically includes a non-metered pentaprism finder and 105mm f/2.4 as normal lens. It is enough to start shooting. A wide range of fixed focal length and zoom lenses, along with TTL-metered and other finders, were available as additional accessories. The system is sometimes referred to as the P67 in online discussions and forums.

The series of cameras consists of the following models:

Pentax 6X7

All cameras have an original dual bayonet lens mount. The inner mount is for lenses with a focal range from 35 to 300mm while the outer mount is for 400 to 1000mm. The shutter is a cloth-based focal plane shutter with speeds of 1 to 1/1000 of a second plus a Bulb mode. The camera supports a Time exposure. To enable this feature the shutter dial has to be set between 1/1000 and X. The shutter release has a locking collar as well as a screw-in cable release connector. For flash synchronisation, there are two PC sockets, one for FP bulb and another for X electronic sync, at 1/30 of a second. The optional left hand grip does contain a cold accessory shoe. The camera is completely battery-dependent, using a 6V PX28/4LR44 battery. The body has no built-in exposure meter.

The film transport uses a single-stroke film advance wind lever. The film automatically stops at the correct frame and does not require a red window. The camera shutter does not work without film. To test fire, open the camera back, and set the film counter dial on a frame number. Close the back while holding the dial. Crank to cock the shutter. The camera locks again when the counter dial has exposed the last frame. A small flush button located under the numeral 7 in the model name on the right-hand front allows the mirror/shutter cycle to be completed if the shutter has been released without battery power. After depressing the button, press the shutter once more to complete the cycle.

The earliest cameras had 21 shots on 220 film. But film transport was poor and it was modified for 20 shots while switch label changed from "10/21" to "120/220".

Pentax 6X7 (MU)

However the vibration problem was reduced by introducing a mirror lock-up feature in 1976. Sliding a switch on the right hand side of the mirror housing upwards releases the mirror. When this revised body was introduced, Asahi also offered to retrofit existing cameras.

Pentax 67

In 1989, a newer revision was released called Pentax 67. The knobs and buttons have changed slightly in appearance design materials and they remained in the same locations with accessory compatibility with the previous models. But the shutter has been changed: the bulb mode now consumes power. However, Pentax did offer a bulb mode modification service, to fix this.

The interchangeable finders have been updated and now use the Pentax nameplate without Asahi. A new revision of the TTL metered prism is offered, it now uses a silicon photo diode instead of a CdS metering cell, the meter specifications remain the same.

Pentax 67II

The Pentax 67II is the newest revision released in 1998. Specifications are very similar to the previous models. The most notable improvement is the built-in right hand grip making handing much easier. The left hand grip from previous models can still be added to the body. A dedicated time mode switch has been added. Using time mode on long exposure do not consume as much battery power compared to bulb mode. The PC terminal for FP flash sync is no longer present, it has been replaced with the Pentax speedlight 5P connector for TTL flash operations. LCD panel is added to this model. It shows information such as frame counter, film ISO, film load status, battery status, shutter cocking, and flash status. The film back still contains the film format (120/220) window, but now has as a emulsion memo holder. The film start mark is now the same for both 120 and 220 film. The 220 format mode can now capture 21 exposures compared to the previous 20 exposures. A new self-timer mode is available, located on the same collar as the on/off dial. It has a 12 second delay with an audible beep. Multiple exposure mode is also available. Battery power has been changed to 2 pcs of modern CR123A lithium.

A newer AE finder is available for this model which offers aperture priority exposure mode along with the basic manual, T and B modes. In AE mode the shutter speed range is from 30s to 1/1000. Pentax also offered a half stop modification to the shutter, so half speeds like 1/45 and 1/90 can also be used in AE mode. A exposure compensation dial with a range of 3 EV. An exposure lock feature allows the exposure settings to retain in memory for 20 seconds. Along with center-weighted averaging metering modes, a spot mode and multi segment metering mode is also offered. Film sensitivity measuring range is also expanded with a range from 6 to 6400 ISO. The viewfinder display uses LED for the display instead of a needle. Also displayed in the finder is shutter speed, aperture, flash status, metering mode and exposure comp. In manual exposure mode, under over indication is shown. Note the AE finder only works with the 67II and the TTL finder from the 67 model is incompatible with the 67II. However other viewfinders (waist level, non-metering prism and magnifying hood) from previous models still can be attached.

Specification

Model Pentax 6X7 Pentax 6X7 MU Pentax 67 Pentax 67II
Introduction 1969 1976 1989 1998
Type 2.25" x 2.75" (6 × 7) Single lens reflex camera, exactly size 55mm × 70mm
Shutter 1 to 1/1000 sec 4 to 1/1000 sec AE: 1/1000-30 sec. (stepless)
Metering No built-in
Optional TTL Pentaprism finder
average metering
Early models CdS metering
Late models SpD metering
Ev 2.5~19 (at ISO100 with 105mm f/2.4)
ISO 2-3200
No built-in
Optional AE Pentaprism finder
Matrix, center-weighted, and spot metering
Ev 2~21 (at ISO100 with 105mm f/2.4)
ISO 6-6400
Flash syncX: 1 to 1/30 of a sec
FP: 1/125 to 1/1000 of a sec
5P: TTL 1/30
Mirror lock up No Yes
Multiple exposure No Yes
Self timer No Yes
Strap lug 4 2
Grip Optional left
Battery PX28/4LR44/4SR44/544A/476A CR123A, 2 pcs.
Battery ext Yes No
Dimensions 184×101×91mm 177×101×91mm 185x108x92mm
Weight 1.29kg 1.21kg