The
Pentacon Six System
by TRA
Is it possible
to modify Pentax 6×7 lenses
so that they
can be used on the Pentacon Six?
This is the opposite of the common question, “Can I use
Pentacon Six lenses on a Pentax 6×7?” You can find
the answer to that question here.
My first question would be “Why would you want to?”
The most obvious answer would be “Because I already have
some Pentax 6×7 lenses and I would now like to use them on
a Pentacon Six.” If that is the case, then it may be
worth exploring. But if you do not already
have any Pentax 6×7 lenses, it may be worth considering
the following:
- the Pentax 67 lenses are harder to find than the Carl
Zeiss and Pentacon lenses for the Pentacon Six;
- they are much more expensive;
- they have generally had heavy and occasionally rough
use by professionals (i.e., they have serious signs of
wear and occasionally superficial damage, dents, etc);
- they are much heavier than the equivalent Zeiss and
Pentacon lenses;
- while optically excellent, they are not optically any
better than the Zeiss and Pentacon lenses;
- obtaining auto aperture operation on the Pentacon Six
with Pentax 67 lenses is difficult and probably
impossible in the space available;
- the cost of the modification probably makes it not
economically viable;
- the selection of lenses available in the Pentacon Six
mount is much greater than the selection in the Pentax
67 mount, so there is little need to turn to Pentax to
get a lens for any particular photographic situation.
The register distance between the rear flange of the
lens that mates with the front of the camera and the film
plane is reported to be 84.95mm with the Pentax 6×7 or
Pentax 67. With the Pentacon Six it is 74.1mm.
So there is very nearly 11mm available for an adapter, plus
that part of the adapter that goes within the throat
of the Pentacon Six and that part of the adapter that holds
onto the Pentax 6×7 lens. So that sounds possible,
rather as making an adapter to mount Pentacon Six lenses on
the Norita is possible (see here).
Update
on adapter to enable
Pentax
67 lenses to be used on the Pentacon Six:
infinity
focus is impossible
I have just received the
following e-mail from David Brown:
“Hello:
I've heard from S.K.
Grimes. It turns out that there is 4.4
mm of material extending from the base of the
bearing surface on the camera (probably part
of the mount), and the auto aperture arm of
the Pentax lens extends 8.8 mm (this moves
side to side, not up and down like the
Pentacon). This is 13.2mm; the focal
flange distance of the Pentax is 84.95 mm, and
that of the Pentacon is 74.1 mm, for a
difference of 10.85 mm. The parts that
stick out from the camera and the lens are
thus larger than the difference in the focal
flange distance, and infinity focus is
impossible.
Adapters can be made without
infinity focus. I assume no one is
interested; if so, please let me know
immediately (it would cost approximately $250,
before shipping).
Trust me, I'm pretty
disappointed with this, so I'm sorry if I got
your hopes up. At least you know why no
adapters exist.
Sincerely yours,
David Brown ”
_________________
If in spite of this serious
limitation you are still interested in
ordering one of these adapters, please e-mail
me at this website and I will forward your
e-mail to David
TRA
16th September 2011
|
Possible
availablility of an adapter
to
enable Pentax 67 lenses to be used on the
Pentacon Six
I received the following e-mail
yesterday:
“I
saw on your website,
http://www.pentaconsix.com/p67lenstop6.htm,
that you
mentioned if someone found a way
to mount a Pentax 67 lens onto a Pentacon
6, to let you know. I'm
currently trying to get S.K. Grimes to
manufacture
custom adapters. I started
shooting my Pentax 67 when the East German and
Eastern European cameras were
harder to come by in the US, but the battery
life on the Pentax 67 is so
atrocious I decided to switch, particularly
since the rebuilt Kievs seem to
be a good bargain. Assuming S.K. Grimes
can
perform the fabrication, there
has been a limited discussion of a
multi-adapter discount, so if
you've run across others like me, pass this
along and perhaps they can get a
deal on mounting Pentax 67 lenses onto
their Pentacon 6 mount cameras.
David Brown”
_________________
If you are interested in
ordering one of these adapters, please e-mail
me at this website and I will forward your
e-mail to David
TRA
15th July 2011
|
However, in 2020 we now know that this is
possible. To find out how, see here.
|