Bronica S2 Mount Nikkor 600mm f5.6 Tele-Lens
Photo thanks to Warren - [email protected]
Few amateur photographers raised on today's autofocus marvels have even
seen a focusing mount lens, let alone used one. The concept is quite
simple. Separate the "lens head" from the focusing and auto-diaphragm
mechanics. Now you can carry several different lens heads and use the one
focusing mount with them. Not only does this save significantly on the
cost of your telephoto lens assemblies, but you also save the bulk and
weight of redundant focusing mounts and assemblies.
The "lens head" is the working optical part of the lens. Many telephoto
lenses are actually long focus lenses, rather than true telephoto designs.
A long focus lens is a simpler design, in which two or more lens elements
are mounted at the front of the lens tube. There is often a substantial
air space between the lens head and the camera body mount. Thanks to this
design, you can put different telephoto focal length lens heads on the
same focusing mount.
This long focus lens design contrasts with a true telephoto lens, in
which the length of the lens is shortened by using additional optical
elements, often near the rear of the true telephoto lens. A true telephoto
lens can therefore be made more compact, but the need for matched rear
mounted optical elements eliminates any easy way to put multiple lenses on
the same mount.
One modest result is that lens head is often a relatively simple design of
only a few elements. Many long focus lenses
of only two elements (flint and crown glasses used to control chromatic
and other aberrations) are used in various refractor telescope designs.
This approach helps keep the cost of longer focus lenses low.
Source: Cooper, Joseph D. and Abbott, Joseph C., Nikon Handbook Series - Lenses and Lens Systems, Amphoto, Garden City, N.Y., 1979.
The above Nikkor lenses are evidently capable of covering the 6x6cm format
on classic Bronicas (S2/EC). The nikon lens mount adapters don't have any
optics in them (both AU-1 and standard focusing units). This design makes
it straightforward to make a lens head focusing unit which mates to the
Bronica lens mount (and other focal plane shutter bodies). My guess is
that only a relatively small number of Bronica lens mount adapters were
made (as shown in Bronica brochures). One nice feature of this parallel
design is that you can use the same lens head on both your Bronica 6x6cm
camera, and then remount it in the AU-1 or standard focusing mount for
your Nikon 35mm SLR mount.
The 1200mm was the longest refractor (glass, non-mirror) lens made by
Nikon for 35mm SLR photography up to that point (1980s). In fact, lenses
in the 800mm and 1200mm range are very hard to use, and not just due to
their size and weight. The close focusing distance is rather long at 61
and 139 feet respectively. Just try to find a fractional diopter telephoto closeup lens in
122mm filter thread too.
Most of us would prefer a more generally useful
600mm f/5.6 lens head and 1.4X or 2X teleconverter to yield an 800mm f/8
and 1200mm f/11 combination. Users of 35mm SLR telephotos need to factor
in the effects of the square format (horizontal angle of view emphasized)
and medium format 6x6cm film size versus 35mm. If you ratio the normal
lenses (50mm on 35mm versus 75mm on 6x6cm) as 2 to 3, a 600mm on 35mm is
more like a 400mm on 6x6cm in use (and 1200mm on 35mm is more like 800mm
on 6x6cm too).
The Komura focusing unit II lets you screw in different lens heads into
the one focusing mount. There are three focusing scales that can be used
(corresponding to each of the three Komura lens heads). You simply twist
the one you want into place. The Komura lenses use manual diaphragms and
preset apertures. These lenses are
evidently designed to cover 6x6cm, based on their significantly larger
weight than similar maximum aperture lenses (e.g., 400mm f/6.3 lens head).
The Komura focusing unit I is used with the very fast 135mm f/2.3 preset
Komura lens. The large rear lens element (50mm diameter) blocks the
auto-diaphragm lever, so the lens is preset. The 135mm lens is 92mm long
(out of unit). Komura also made a relatively fast preset 200mm f/3.5
(1/3rd stop faster than f/4) which mounted in
focusing unit #1. The
focusing mount has distance scales for both the 135mm f/2.3 and 200mm
f/3.5 lens heads. [Thanks to Larry Life for these details].
The simplest tube design would require manual or preset operation of the lens aperture. By
having the photographer stop down manually, the lens design can avoid
complex couplings needed to provide automatic diaphragm operation. Since
most long telephoto lenses are used on rigid tripod mountings to avoid
camera shake, this extra step is not as cumbersome or time consuming as it
might seem. The Komura focusing mounts for Bronica use this simple and low
cost manual design.
Naturally, you could design a focusing mount which would permit
auto-diaphragm operation. And Nikon did so with its BR-1 focusing mount
design. The focusing mount becomes more complex and costly, and
due to the 1200mm range of Nikon's lens head choices, even larger.
Finally, you can have an auto-diaphragm mounting which has a "fast
focus" or "follow-focus" action. Novoflex is famous for its series of
follow-focus bellows mount telephoto lenses. In this case, the telephoto
lens head is mounted on a bellows. The bellows can be an auto-bellows
model, which has coupling rods to enable automatically stopping down the
lens aperture ring when shooting. But since you are using bellows, you can
also devise a handgrip which lets you focus by squeezing or releasing
tension on the handgrip. This trick gives you surprisingly fast focusing
coupled with a convenient telephoto lens design. These Novoflex
lenses were usually mounted on a
gunstock or similar steadying platform. You just pointed the lens at the
subject, squeezed the handgrip to focus, and pushed the cable release to
shoot. This ancient technology was very nearly as fast as today's
autofocus cameras in the right hands!
| Novoflex Follow-Focus Lenses | |
|---|---|
| F/l | f/stop |
| 280mm | 5.6 |
| 340mm | 5.6 |
| 400mm | 5.6 |
| 500mm | 5.6 |
| 600mm | 8 |
| 680mm | 8 |
The good news is that Novoflex made adapters to use with their bellows for
classic Bronica cameras, among other medium format focal plane camera
mounts. Unfortunately for medium format users, the Novoflex lenses were
designed to have high center sharpness, at the expense of lower resolution
in the corners. This tradeoff makes sense for most telephoto uses, since
the images are usually cropped anyway after shooting to improve
composition. But while this drop in sharpness is not too bad on 35mm, it
may be objectionable for some users and some uses on medium format.
Besides Novoflex, other such as Burleigh Brooks Inc. (of North Hollywood,
CA.) offered telephoto lenses of up to 640mm in similar gun-stock and
trigger focus mountings (perhaps Novoflex lenses under their import
label?). Birns and Sawyer (of Los Angeles, CA) also provided their Omnitar
telephoto and long-Tom lenses (I'm not making that up!) in Bronica and
other medium format focal plane mounts too.
Many others have reused Leitz
long focus lens heads meant for Visoflex reflex viewer mounting on Leica
35mm rangefinders on their medium format cameras with success too. I have
used a Nikon rangefinder 135mm lens head on my classic Bronica cameras too
(see photo below).
Naturally, the $10,000
US Zeiss 500mm f/8 telephoto lens for the Rollei SL66 is a better lens
than a remounted 500mm f/8 T-mount lens costing only $129 US in 35mm
mounts. But the remounted 500mm T-mount lens combo is available for many
focal plane shutter medium format cameras such as Pentax 645 for under
$400 US! If you are handy, you can buy a used 500mm f/8 multicoated lens
and mount it (e.g., in an extension tube mount) for under $100. Before you
sneer at the possible lens quality from a $129 multicoated 500mm f/8 lens,
you might want to know that this lens scored all excellents for center AND
edge resolution (in Popular Photography tests).
Other lenses have been converted to use on various focal plane shutter
camera bodies, including the classic Bronica S2/EC series. Our homebrew lens hacking pages describe many of these
efforts and success stories. I have the 135mm f/4 nikkor, a 320mm APO, a
400mm f/6.3, and the 500mm f/8 for my Bronica cameras among others - so
far. The total cost for all four of these telephoto lenses was under $300
US, so the interest in this approach among budget medium format users is
understandable.
Other focal plane cameras are also easily used with long focus lenses,
provided you can provide a focusing mechanism and lens aperture control.
The 500mm f/8 T-mount (and companion 400mm f/6.3) lens has both of these
features. The 500mm is also easy to convert, since the rear tube unscrews
in many models, making it easy to make a second tube to mate with the lens
and the camera mount. An extension tube is often used as a start to making
such a lens adapter. In fact, one of my tricks is to use one such
extension tube with a series of different sized lenses and tubes, each
fitted to mount with infinity focus set on the one extension tube adapter.
Unfortunately, lots of cameras use leaf shutter rather than a focal plane
shutter. Adapting such lenses is more costly and difficult, as you have to
supply a shutter as well. One option is to use an accessory leaf shutter
accessory used with microscopes and telescopes. This often pricey
accessory makes it possible to connect your Hasselblad 503, Rollei 6008i,
or your Kowa 6/66 to telescopes, microscopes, or other lenses and still
have a standard shutter.
For cameras or users without this accessory, I suggest finding a damaged
normal lens and removing the glass. Now you can put a metal stacking cap
into the lens threads (e.g., 67mm stacking cap). Drill and mount the
desired lens so as to achieve infinity focus. You will have to stopdown
the lens manually or with preset rings (if present). I call this a
"shutter lens", as it is a lens used as a shutter.
You can also use some long lenses for view cameras and 6x9cm folders on
many cameras. Simply mount them as a regular lens head, and focus with the
shutter open (many view camera lenses have this feature with an extra
release arm). When ready to take a photo, set the camera to Bulb or Time,
trip the shutter (and hold if Bulb), and then trigger the leaf shutter. A
double cable release makes this easier and faster to do than to
say.
Hi Bob,
Yes, you are correct. Starting somewhere around the MID-1960's Nikon
introduced what they called the "TELE-NIKKOR" Lens System, which consisted
of 4 separate lens heads and one focusing mount adapter {which was
redesigned several times during its lifetime}. The thinking at the time
was how economical this would be. The photographer would only have to buy
one focusing mount, thus saving money so he could afford to have more than
one lens head. These mounts were made available for both the Nikon F mount
and the Bronica S2 mount {after removing the helicoid focusing mount from
the camera body, used for the smaller Bronica/Nikkor lenses}.
To answer your question about whether or not any of these "TELE-NIKKOR"
lenses had "Pre-set" or "Manual" Diaphragms, the answer is "YES" !!! The
800MM F/8.0 & the 1200MM F/11.0 Nikkor's both had a "MANUAL" diaphragm
ring near the rear of the "LENS HEAD". In the case of the 800MM lens you
could go either way. You could use the auto-diaphragm on the focusing
mount or you could use the manual diaphragm on the lens head, so long as
you stayed within the aperture range of either diaphragm system. The
diaphragm ring on the lens head offerred smaller apertures for increased
"Depth-of-Field". In the case of the 1200MM it was manual diaphragm only.
The aperture ring on the focusing mount was to be set to wide open and
left there. However, if you were going to be using either F/11 or F/22,you
could set the manual diaphragm ring on the lens head wide open to F/11 and
then set the auto-diaphragm ring on the focusing mount to F/11 or F/22 and
just have at it. You see the auto-diaphragm on the focusing mount offerred
lens apertures from F/4.5-F/22,whereas the manual diaphragm on the 800MM
lens head had apertures ranging from F/8-F/64 and the 1200MM lens head had
manual diaphragm apertures ranging from F/11-F/64.
Hope that clears up a lot of things concerning those old Nikkor lenses.
However,if at anytime you have a question concerning any of these lenses
please don't hesitate to ask,as at one time I was classified as a "NIKON
SPECIALIST" by E.P.O.I. {Nikon Distributors at that time}. Please don't
ask me anything about the new stuff{from Nikon F3 to present}because I
don't know anything about these newer products.
One word concerning the adaptation of one of the Tele-Nikkor lens heads to
the focusing mount made for the KOMURA Teles {300/400/500MM}. I don't
think I would try that one, because that mount screws into the threaded
portion of the Helicoid focusing mount for the smaller lenses. The weight
of these Nikkor lens heads is such that I am afraid it might rip the mount
right out of the camera.
As for 120 Kodachrome, I haven't shot a roll of that since I got my FIRST
Bronica S2A back in August,1971. So like yourself, I've been forced to
fall in love with 120 Ektachrome EPR 64 and like yourself I have found
that it will more than do the job.
See Ya,
Rick
From Bronica Mailing List:
Date: Wed, 21 Mar 2001
From: [email protected]
Subject: Komura 300/400/500 for S2A and Uni Helical #2
Does anyone know whether the Komura teles that are designed to work
with the Uni Helical #2 were all the same, or did they come in
slightly different versions?
I have a beautiful 300mm/f:5 head that I picked up in virtually new
condition (old stock from B&H originally priced at $450 (!), unloaded
by B&H on eBay for cheap), and after hunting around for the helical
or a different head with helical for a while, I just decided to by
another 300 with a helical, since these are easy to find, keep the
new head and the helical and sell off the older head. As it turns
out, the newer head is also an optically better example of this lens.
Well, it seems that the nicer head is a slightly different thread
from the helical--same diameter, but it doesn't screw in. It might
just be rough or maybe the threads are slightly bent, but I don't want
to force anything and risk cross-threading.
Any suggestions? Can anyone confirm or disconfirm that they made the
same lens with two slightly different threads?
David Goldfarb
From Bronica Mailing List;
Date: Wed, 21 Mar 2001
From: [email protected]
Subject: Re: Komura 300/400/500 for S2A and Uni Helical #2
David,
Komura made a variety of similar lenses and some for Bronica S2 types.
There are different versions in the same focal lengths and they may not
all fit the same mounts.
I had a Komura focusing mount for pre-set lenses not designed for the long
focus lenses.
And I had a 400MM f6.3 which screwed into the normal Bronica mount.
Yes, they are not all the same.
- Sam