It is perhaps inspired by the 1957 East German 6×6 KW Praktisix and its successor, the Pentacon Six, although the horizontal SLR concept can be traced back to the 1933 Ihagee VP Exakta.

More than forty years after the original camera introduction a wide selection of lenses is still available, together with the latest Pentax 67 II variant.

Users familiar with the diminutive cousins in the 135 format would find the Pentax 6×7 an easy transition due to the layout of the camera.

The most obvious difference with common SLRs is the location of the shutter speed knob being at the left hand top.

The latter (outer) was provided for use with larger and heavier telephoto lenses and allowed the body to rotate and lock in any of the four positions.

The Pentax 6×7 is able to use either the 120 or 220 film rolls, which produce ten or twenty frames, respectively (twenty-one for the 1969 version).

Power is provided by a 6 volt PX28 (originally Mercury-specified 1968, and Silver Oxide 1971), but equal substitutes PX28S/4SR44.

As with many systems of the era, the mirror and cloth curtains are mechanically-driven, the timing of the shutter being electrically governed by transistors and a magnet.

The combination of resistors routed by the speed setting determine the length of time the magnet remains engaged.

The large cloth curtains as well as the size of the exposure area limits the maximum flash synchronizing speed to 1⁄30th of a second.

However, one can test the shutter by rotating the counter dial away from the empty position while the film door is open and then by closing the film door while still holding the dial, thus facilitating the unlocking of the advance mechanism and operation of the shutter.

As well were changes to the spool release mechanism, where it was an improvement from a checkered friction operated surface to a more convenient flip handled method and the center posts that held the film spools lost their angled profile for a more controversial straighter angle that improved film feed accuracy, but caused some difficulty in speed of spool placement during film reloading and also to prompted some to seek services to custom grind the posts.

Lesser known for the later original 6×7 and 1990-era 67 cameras was a special factory modification that would allow the bypassing of part of the frame counter mechanism ("duality-prevention lever") for deliberate double exposures, though not many were made with this feature, and estimate of only a few hundred may exist.

This was a popular request from astronomers that needed the camera to expose for times greater that the batteries could allow.

The demand for this modification was reduced when the availability of a third-party adapter plate that could override the need for a battery, and mimic the cycle of the mirror release and shutter opening by a simple plate that employed two shutter release cables.

Polaroid back / Foscher-adapted bodies were a non-factory modification that was usually applied by authorized service centers, and was a popular enhancement used by studio photographers for lighting tests.

The special modification allowed switching in, out of the Foscher back, to a normal pressure plate for roll film without the need for a service technician to partially disassemble the hinge, as well as re-attaching the leatherette.

Some reports of mixed-and-matched part factory release bodies also existed, as well as mix / match as a result of authorized servicing mandating the exchange of the older advance system for the newer version.

Later lenses would abandon the Takumar branding in favor of "SMC Pentax 67" and include modifications to optics, functional and cosmetics.

Most of the lenses are "auto-aperture" type to allow for the brightest viewing and focusing of the lens for composition of the subject.

In turn the ring has a chain connected and running up into the finder bay and linked to a tab under spring tension.

[5] With either leaf shutter lens set to LS mode, the TTL meter on the Pentax 67 will not operate.

The through-the-lens (TTL) metering pentaprism viewfinder included a knurled shutter dial ring with fitted case.

This inner pin is connected to an electrical toggle inside the body that switches the current from body-grounded to bay connector to activate the secondary circuit.

The physical difference of the TTL meter to the regular prism is the coupling arm that extends to the shutter speed dial.

The lens is allowed to stop-down and the light is directly measured, however, the shutter speed dial link operates the same in MAN mode.

It attaches to the two lugs / posts at the front of the camera and is secured by tightening a finger-operated bolt onto a stud found at center.

The grip is removed by loosening and lifting the bolt to slide off in a downward direction to allow the lugs to clear the keyhole slots.

Clip-on hoods were introduced at about the same time as the released of updated 6×7 lenses started to wear the 67 engraving.

Camera Trunk was a steamer trunk-style case that was marketed to carry two bodies and four lenses that were secured with a lockable bayonet platform.