Osaka 400mm and 500mm telephoto lenses. Excellent lenses
imported by Bromwell Marketing, my field experience
with them was very favorable. They are quite compact
and lightweight and both have a very short flange-to-film
distance. Images seemed very sharp, with good contrast
and they are also priced very reasonably.
I shoot multiple formats
ranging from 35mm to 4x5, depending on subject matter and my client's
needs, but I love my teles. Whether it's getting up close and
personal with a yellow-rumped warbler or attempting to optically isolate
some element out of the chaos before me, my telephotos do yeoman duty.
Much has been written in Shutterbug, and other photographic publications,
regarding telephoto lenses for 35mm. However, telephoto lenses for
larger formats, and view cameras in particular, remain a mystery even
to many of those who regularly shoot with these cameras. Let's
shed some light on these remarkable tools and see if maybe there's
a place in your camera bag, not to mention your heart, for one of
these big berthas.
The Nikkor T-ED 500mm and the Fujinon TS 400mm. You can
see how much of the lens has to fit inside your camera's
bellows. With smaller field cameras this could negate using
either of these lenses. If you're not sure, consider
renting the lens you're contemplating to make certain
it's going to work for you.
first clear up a common misconception and see how telephoto lenses actually
work. Many photographers refer to any lens that is longer than normal
as a telephoto lens. In fact, if the lens' physical length, when
focused at infinity, and its focal length are equal it should accurately
be called a long lens. Let's compare two mythical lenses, one a
300mm Wundertar and the other a 300mm Tele-Wundertar. If you focus the
300mm Wundertar on your 4x5 camera at infinity, the distance from the
film plane to the middle of the front element will be approximately 300mm,
or 12". The lens is therefore a long lens.
It is not a telephoto lens even though it is considerably longer than
the 150mm normal focal length for a 4x5 camera and should not be referred
to as such. However, the Tele-Wundertar focused at infinity, measured
in the same way, will be physically much shorter than 300mm due to its
telephoto design. Both lenses will have identical angles of view and will
include the same amount of the subject in the shot. But the tele lens
will require considerably less bellows extension.
example of using a telephoto to achieve a tight cropping
at the Malakoff Diggings State Historical Park in California's
Gold Rush Country. Any other camera position would have
meant shooting from the canyon floor.
Photos © 2002, Joseph A. Dickerson, All Rights Reserved
Tele Lens Design
The principles of telephoto lens design were discovered by Barlow over
150 years ago. In 1891 these principles were simultaneously applied to
photographic lenses by Dallmeyer in England, Dubosq in France, and Meithe
of Germany. Barlow discovered that the use of a negative rear lens element
allowed lenses to be designed that had a shorter lens-to-film distance
than a normal-type lens of the same focal length. With studio monorail
cameras this is rarely an advantage, but with compact field cameras the
bellows draw is often inadequate for longer focal lengths. Closer focusing
requires the bellows to be extended even further, something not possible
for many field cameras on the market today. A telephoto 300mm lens needs
less bellows extension, which allows a camera with a 12" bellows
to focus closer than infinity. This becomes even more critical when the
photographer wants to employ still longer focal lengths.
One other salient point is that there is no other advantage to using telephoto
lenses. They are not inherently superior, or for that matter inferior,
to long focal length lenses. Their only advantage is their physical size.
There are, however, some aspects of their use that can be confusing.
Using telephoto lenses with a rollfilm adapter increases
the telephoto effect. This old shack was shot with a Fujinon
400mm lens with 120 film in a Horseman 6x12 film holder.
Telephoto Lenses And Close-Up
When calculating the exposure compensation required for close-up photography
with a view camera and a non-telephoto-type lens you divide the bellows
extension (squared) by the focal length (squared) and the result is the
bellows extension factor. A factor of four indicates a two f/stop increase
is required, a factor of two a one f/stop increase, etc. But with a telephoto
lens measuring the bellows extension to the lens itself will result in
an inaccurate reading. Here's the trick. With a telephoto lens you
first need to measure one focal length forward from the film plane or
ground glass while the lens is focused on a distant object. Note the difference
between the measured focal length and the distance to the lensboard. Then,
when you are computing bellows extension add that difference to the measured
bellows extension. It's confusing at first but when you work through
it a time or two it will make sense.
The Nikkor T-ED 270mm has a large enough image circle to
covaer 4x5 with a little to spare. This makes it ideal on
a medium format view camera as it provides plenty of movements
for roll film. Considerable front rise was used in this
We all use the Scheimpflug
rule when trying to maximize sharpness with a view camera. You remember,
if the plane of the film, the plane of the subject, and the plane of sharp
focus meet at a common point you have optimum image sharpness. Well, Scheimpflug's
rule still works with telephoto lenses but it's trickier because
the nodal point is hanging out there in front of the lens instead of being
inside the lens where it belongs. Essentially you'll need less tilt
than with normal lenses, and it takes some extra fiddling about to get
it just right.
One other thing about telephoto lenses is that they tend to have smaller
image circles than comparable long lenses. Watch carefully for vignetting
or image falloff as you start to use camera movements, and always check
the corners of your ground glass after you've stopped down.
I have recently begun using a Nikkor T-ED 270mm lens on
my medium format Gowland Pocket View. I find this lens to
be somewhat sharper and considerably contrastier than the
1960s-era lens it replaced. The modern multi-coating probably
accounts for much of this improvement. Test older lenses
before you buy to make sure that the performance is adequate
for your needs.
It's All In The Chart,
I've prepared a reference chart that lists some common large format
telephoto lenses and their features. The chart is not meant to be all-inclusive,
but I've listed as many lenses as I could find data for. Some are
available new (see chart, page 80) and some will only be found on the
used market. You might try finding them in the back pages of Shutterbug
or at your local camera swap meet. If you're contemplating buying
an older lens be sure and run through the shutter speeds to see if they
seem accurate and check the glass by shinning a light through the lens
while the shutter is open. If you see discoloration, separation, scratches,
or fungus in the glass (fungus will show up as haziness in the glass)
you should probably pass on the lens. If you find some minor problems
but you've really just got to have it anyway see if you can return
it if it fails a practical shooting test. By the way, older shutters will
often slow down from lack of use and all they really need to get them
going again is exercise. This can often serve as leverage to help you
negotiate the price downward.
The Nikkor T-ED 270mm made this composition. There were
too many distracting elements just outside the image area.
They could have been eliminated by moving the camera closer
but the camera would have to be in the middle of traffic.
One important characteristic
that won't show up in my chart is bulk. View camera telephoto lenses
are not petit. Quite the contrary, they're big and much of that
bulk needs to fit inside your camera's bellows. Telephoto lenses
also tend toward obesity, and that weight hanging off the front of your
lightweight field camera may just be the last straw, so to speak. If you
want to use a telephoto lens on your 4x5 field camera check first to make
sure the front standard has the necessary strength to support it. The
extra weight cantilevered off the front of the camera may also mean you'll
need to upgrade to a sturdier tripod to eliminate camera shake. No sense
spending good money on a sharp telephoto lens and then destroying image
sharpness with vibration.
Where To Buy Telephoto Lenses
Osaka Lenses and Other Cool Stuff
3 Allegheny Center #111
Pittsburgh, PA 15212