Pentacon Six or Pentax 6x7?
Having eliminated the Norita, I considered the Pentax 6×7. Should I buy one of these instead of a Pentacon Six?
A news item in the UK publication “Amateur Photographer” in the late 1960s indicated that the famous Japanese 35mm SLR manufacturer Pentax was to make a medium format 6x6 camera based on the Pentacon Six. This turned out in fact to be the Pentax 6×7, which produced 10 exposures 55mm x 70mm on 120 film (or 20 on 220 film). It was hailed by the manufacturers as the “ideal format” for magazine pictures, as they claimed that most 6×6 images were cropped in order to fill magazine pages. Their literature stated that although the image size was only 21% larger than a full 6×6, once the 6×6 image had been cropped to a vertical format, the Pentax 6×7 original was in fact 50% bigger than it.
The first impression when one picks up a Pentax 6×7 is that it is
big and heavy – much bigger and heavier than the
published in 1976 for the German market
|The Pentax 6×7 with the plain (non-metering) prism.
Note the slot (arrowed) in the shutter speed dial in which a pin from the metering prism located, in order to transfer to the meter the information on the shutter speed that has been selected .
If only Pentacon had thought to do this! Pentacon Six lens mount users had to wait for the Exakta 66 for the camera’s shutter speed to be coupled with the TTL meter, and when it came, Exakta chose a more sophisticated electronic coupling.
The Pentax 6×7 has an electronic shutter and is totally battery dependent – if the battery fails, the camera is dead – and battery consumption is reported to be high! The shutter is also very noisy – not suitable for wildlife shots. The shutter speed range is the same as on the Pentacon Six: B, 1 sec – 1/1000 plus X. Flash sync is 1/30 second – the sync speed for which the Pentacon Six was condemned by many reviewers! However, the camera with a basic, non-metering prism was loved by some fashion photographers aiming at dynamic shots with a hand-held camera, and magazine editors loved the format.
Like the Norita, and unlike the Pentacon Six, it has an instant-return mirror.
There is no delayed action lever.
The large mirror also causes a lot of vibration (and presumably a fair proportion of the noise) at the end of its travel (just as the shutter fires!). An “Amateur Photographer” review years later (on 23rd January 1999) said that this “will cause camera shake at speeds which you would normally consider handholdable”. Towards the end of the 1970s a mirror lock up was added to the camera. This enables vibration to die down before releasing the shutter – fine for macro, architectural and still-life shots, but of no use for hand-held shots or anything that moves.
A review on luminous
landscape.com written in late 2001 states that further
vibrations are in fact caused by the shutter itself,
so even using the mirror lock up will not solve the problem:
|“what's happened here is that the shutter has bounced, as all shutters do. So, there have effectively been two exposures. One during the opening of the shutter and the second during the closing, at which point the camera had essentially rung like a bell thus causing the second image.”|
The reviewer goes on to say that that the Pentax 67 can be
|“only with normal to short lenses, and only in very good light or with fast film”.|
For most combinations of lenses and films it is a tripod-only
camera. Worse, the reviewer goes on to state:
|“Pentax states in their manual that the tripod should weigh more than the camera. I'd say the tripod and head should weigh at least twice as much as the camera and lens combination for ultimate rigidity.” [emphasis mine]|
The reviewer concludes:
|“this is best a tripod mounted camera, especially with long lenses and slow shutter speeds”|
If you plan to take your camera out on hikes or on holiday, the implications of this are worth considering.
The Pentax 6×7 and the Exakta 66, reproduced to approximately the same scale [C372-25A & scan from Pentax brochure]
The basic body does not have a pentaprism, but in practice the camera is designed for use with one – it is difficult verging on the impossible to use the camera for vertical images without one. Many models were sold with a plain prism, although a fully-coupled TTL metering prism was available. This is an improvement on the Pentacon Six non-coupled prism.
Interestingly, the reviewer on Luminous Landscape (see link,
above) informs us that
|“The meter prism is almost a must with this camera,
but be aware that it only shows 90% of the full
frame recorded on film.”
(This is precisely the same as one of the criticisms that has
been made of the Pentacon Six prisms. See details here, at the bottom of the
|A waist level finder and a magnifying head were also
available for the Pentax 6×7. These might, in
particular, be useful for macro or studio work (with
horizontal images only!), not the hand-held action shots
for which the Pentax 6×7 was principally advertised.
The folding “waist level” finder is on the left.
This contains a 1.6x magnifier.
With their wide experience of lens design for their 35mm SLR
cameras, Pentax were able to produce an extremely impressive range
of lenses for the new format:
|Focal Length||Aperture Range||Angle of view
|Elements||Closest Focus (m)||Filter size (mm)||Auto/Manual Aperture||Weight (g)|
|35mm||f/4.5 – f/22||180°||11||0.45||(2)||Auto||920|
|55mm||f/3.5 – f/22||78°||8||0.45||100||Auto||920|
|75mm||f/4.5 – f/22||61°||5||0.7||82||Auto||600|
|105mm||f/2.4 – f/22||45°||6||1.0||67||Auto||628|
|135mm (3)||f/4 – f/22||36°||5||0.85||67||Auto||767|
|150mm||f/2.8 – f/22||33°||5||1.5||67||Auto||768|
|200mm||f/4 – f/22||26°||4||2.5||67||Auto||900|
|300mm||f/4 – f/45||17°||5||5.0||82||Auto||1,425|
|400mm||f/4 – f/45||12°||5||8.0||77||Manual||2,570|
|600mm||f/4 – f/45||8°||6||12.0||77||Manual||6,000 (4)|
|800mm||f/4 – f/45||6°||6||20.0||77||Manual||17,700|
(1) As the frame size and image diagonal are larger than
in the 6×6 format, the angle of view is slightly wider, too.
To compare with the angle of view on 6×6 format lenses, click here.
(2) UV, Y2, O2 and R2 built in
(3) Macro lens
(4) The Pentax 6×7 may have been aimed at the dynamic user taking hand-held action shots, but no-one will be hand-holding these lenses! Even carrying them from the car might be a problem! The 800mm lens makes Carl Zeiss Jena's 1000mm Mirror lens seem light by comparison. I suspect that some of these lenses were only made to order, and no doubt had prices in U.S. dollars close to the weight in grams!
(5) Y2, R2 and ND built in
In addition – rather like with the Norita – a lens with built-in
leaf shutter was offered. This enabled flash sync at all
speeds. Details are as follows:
|Focal Length||Aperture Range||Angle of view||Elements||Closest Focus (m)||Filter size (mm)||Auto/Manual Aperture||Weight (g)|
|90mm||f/2.8 – f/22||53°||6||0.85||67||Auto||610|
(By the 1990s, the 90mm leaf shutter lens had been withdrawn, and replaced with a much longer focal length 165mm f/4 leaf shutter lens.)
All of the lenses have Pentax’s SMC multi-coating.
Other lenses have been added over the years.
Inspired no doubt by the 1930s 35mm Contax rangefinder cameras (which had in turn been copied by Nikon in the 1950s), the Pentax 6×7 had two lens mounts: a smaller one for the shorter lenses, and outside it a larger mount for the much heavier lenses.
An extremely wide range of accessories were produced for the Pentax 6×7. In 1976 the following items were listed:
The Pentax 6×7 system was impressive. Yet I took the decision not to buy into it. My reasons were:
To go back to the introduction to the cameras, click here.
To return to the section on the pentaprisms, click here.
To return to the interview with the author, click here.
© TRA November 2005
Latest revision: February 2017