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Contents
Light in the Dark:
Fort Point San Francisco 2
Planar T* 1,4/50 ZE -
A Standard Lens with
a Difference 4
Manual Focusing with
AF Camera Systems 6
New York City Impressions
With the Distagon T* 2,8/21 12
July 2009Carl Zeiss Camera Lens Division
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Carl Zeiss July 2009 Page 2
Camera Lens News No 32
Light in the Dark: Fort Point San Francisco
Directly under the famous San
Francisco Golden Gate Bridge is the
Fort Point National Historic Site. This
fort was built to protect the SF Bay
from the Confederate army during
the U.S. Civil War, though as far as
we know it was never used in military
operations. Today Fort Point is open
to visitors three days per week and
we have taken quite a few photos
there over the years.
The challenge taking interesting
photos at Fort Point is the high
dynamic range (light from the outside
and quite dark structures) and the
need for ultra wide angle lenses. We
deal with the high dynamic range
using HDR techniques (later more)
and the Distagon T* 2,8/21 ZF on a
Nikon D700 full frame camera was
ideal to photograph the interior
architecture. We were very pleased
that all the scenes we wanted to
capture could be photographed using
the Distagon T* 2,8/21 ZF lens. One
could say that 21mm seems to be
a very good focal length for indoor
photography in general. It has a
wide angle of view of 90° without
getting to the extremes. Wider angles
can lead to more distortions than we
would like to accept.
Taking HDR photos requires taking
multiple exposures from a sturdy
tripod. An example of a typical
exposure range is shown here:
For this kind of scene we need at least
3 shots with -2.0Ev, 0EV and +2.0EV
exposures (more could be even
better). As you can see in the middle
exposure, the shadows are too dense
and the highlights are blown-out.
Even the -2EV underexposed photo
still has slightly aggressive highlights.
The +2EV overexposed photo
shows good shadow detail, but the
highlights are lost completely. That
the Distagon T* 2,8/21 ZF is a manual
lens is not problem at all, because
these kind of photos are always
best shot using manual focus. We
generally used a hyperfocal setting
for the photos at Fort Point, because
there was not any interesting
detail closer than 2m and we used
f/8 for nearly all our photos.
Carl Zeiss July 2009 Page 3
Camera Lens News No 32
We use the Photomatix software
to combine these three photos into
one HDR image. HDR images (32 bit
floating point) can store a tonal range
that is even much higher than we
needed in this case. What to do with
these HDR images if their content
cannot be printed on any medium?
The answer is Tone-mapping. We
use the Photomatix Details Enhancer
tone-mapping tool to map the larger
tonal range into a printable version.
Here is our result from this two-step
process (HDR generation and tone-
mapping):
The final image shows open shadows
and no clipped highlights. The next
photo was from the same session and
created using the same technique.
Overall we can report that the
Distagon T* 2,8/21 ZF on a full frame
camera and HDR with Photomatix
proved to be the right tools for our
work at Fort Point. We plan to work
more using this lens and apply its
angle view on our subjects.
After our session inside of Fort Point
we took this shot of the Golden Gate
Bridge just outside of Fort Point.
It shows that 21mm can be a very
creative focal range.
Text and photos by Bettina +
Uwe Steinmueller
Carl Zeiss July 2009 Page 4
Camera Lens News No 32
The next test for the Planar T* 1,4/50 ZE
was a series of portrait shots I took
for a manufacturer of specialist
skateboards – so-called longboards –
in Dusseldorf. I had previously tended
to work with autofocus zoom lenses
and occasionally with autofocus
prime lenses, so the manual focus
took some getting used to at first,
Planar T* 1,4/50 ZE - A Standard Lens with a Difference
I had been toying for a while with
the idea of getting myself a 50 mm
prime lens, but with autofocus. That
was before I got the opportunity to
test the ZEISS Planar T*1,4/50 ZE with
manual focus, and now I wouldn‘t
change it for the world!
The first project for my new lens
was a fashion shoot on the topic
of „My home is my castle“, which I
worked on with the photographer
Thea Fischer. The location we used
was an old Russian military hospital
near Berlin. The shoot took place at
-5°C in snowy, icy conditions and
was a real challenge in so many
different ways, but it really showed
me just how much I could depend
on my new lens. I think the thing
that impressed me most about the
Planar T* 1,4/50 ZE was the superb
image quality it achieved even at
wide apertures.
The Planar T* 1,4/50 ZE also delivers
bright images with excellent contrast
and natural color rendition, a fact
that was particularly appreciated
on this shoot. The subjects really
come to life with the extreme con-
trasts between light and dark and
the exciting color contrasts. but I was impressed by the precision
of the available settings. The extra-
large rotation angle for high-precision
focusing provides major benefits for
all sorts of applications. Thanks to
these technical features, I had more
time to devote to each subject and
more control over the end result.
Fashion shoot „My Home is my Castle“ in collaboration with photographer Thea Fischer.
Carl Zeiss July 2009 Page 5
Camera Lens News No 32
Both shoots showed me that working
with the Planar T*1,4/50 ZE makes
you more conscious of your image
composition. These photographs
ultimately have more of a sense of
harmony than photographs taken
with an autofocus zoom lens.
Personally, I came to the conclusion
that the Planar T* 1,4/50 ZE is the
perfect lens for me, not only thanks
to its superior image quality, but also
due to the broad scope for creative
design that the manual focusing
offers. When it comes to portrait
shots I prefer to be close to my
subject, and this lens is the ideal
choice for that technique. It may
take a bit of practice to speed up
the process of working with it, but
it is worth the effort. However,
one thing I would recommend is
swapping the ground glass screens
included with the lens for screens
with a split image rangefinder
and microprisms, since this makes
it far easier to check the focusing.
All the pictures here were taken
using a Canon EOS 5d and the
Planar T*1,4/50 ZE.
Portrait of a longboard manufactorer in Dusseldorf.
Sabrina Weniger obtained
a degree in pedagogy from
Dusseldorf‘s Heinrich-Heine
University. At the same time she
was taking photography courses at
colleges in Cologne and Dusseldorf
and attending workshops in digital
photography and image editing.
During a trip to New York City in
2004 as part of her studies, she
decided to live her dream of
becoming a photographer. A jury
consisting of photographers, press
representatives and members of
the “Photo+Medienforum Kiel”
chose her as the winner of the
Kiel Scholarship in 2005. Viewers
of her photos are immediately
struck by the natural, simple
pleasure that she takes in her
work, which features tranquil
moments enriched with a spirited
dose of joie de vivre.
Carl Zeiss July 2009 Page �
Camera Lens News No 32
relevance for photography and image
reproduction.
Precision focusing
One of the key links in the chain of
successful image rendering is the
precision with which the lens focuses
on the main subject. Generally
speaking, a photographic lens only
provides optimum rendering at
maximum image quality of a two-
dimensional surface. This surface
runs exactly in parallel to the film or
sensor in the camera. Depending on
the magnification and the selected
aperture, a certain range both in
front of and behind the point of
optimum focus is also considered
to be „adequately sharp“. In this
context, the magnification refers
to the ratio between the image
produced by the lens and the object
being photographed. Thus, the focal
length of the lens, the shooting
distance and the size of the film or
sensor are responsible for the so-
called depth of field. The focusing
Manual Focusing with AF Camera Systems
region designated as the depth of
field is the extent of the range in the
object space of an imaging optical
system. This region is rendered in
acceptably sharp focus on the focal
plane.
You can read about the effect that
slight defocusing has on image
quality in the article „Measuring
lenses objectively“ which appears in
Camera Lens News no. 30 starting
on page 24. This article shows
how important precise focusing is
whenever a photographer intends to
produce big enlargements or requires
optimum quality for any other
reason, and not only when using
wide apertures.
What should I focus on?
The question of what main subject
to focus on obviously comes down
to the taste of each individual
photographer. Nevertheless, there
are not likely to be any significant
differences in opinion when it comes
to choosing the optimum focal point
for photographs of a painting or
of a mountain chain that stretches
into the endless distance. Equally,
traditional portrait photography
continues to reserve maximum
sharpness for the model‘s eyes.
Tinkering with sharp focus and blur
is one of the most fundamental
creative aspects of photography. The
fact that our environment is three-
dimensional means that people can
have differing views on what should
be depicted with clarity and what
should appear in a sketchy or blurred
form, for example when searching Photographer Sabine Unterderweide
Superb image quality in today’s
world of photography is fostered
by a whole host of different factors
such as the high numbers of pixels
in digital SLR cameras, large format
sensors in full-frame 35mm format
or traditional almost-medium
format, intelligent image processing
techniques and noise reduction
algorithms.
The results are also dependent on
how the camera interacts with the
lens, which is why high-grade optics
have such a vital role to play in
fulfilling photographers’ increasingly
sophisticated demands with regard
to image quality.
The weakest link
Achieving top-quality shots with
high-resolution cameras means
keeping all the parameters that have
a direct or indirect impact on image
quality within strict boundaries. The
idea that “a chain is only as strong
as its weakest link” has particular
Carl Zeiss July 2009 Page 7
Camera Lens News No 32
for the right focus in a group of
people seated around a circular table
under difficult lighting conditions.
Checking the depth of field using
the camera‘s preview button is one
technique that can be useful. Good
results can also be achieved by the
use of face recognition software in
modern cameras that focuses the
lens on the nearest person, especially
when using compact cameras with
small sensors and short focal lengths.
However, this is clearly inadequate
for the purposes of carefully arranged
photography using SLR or rangefinder
cameras, where high apertures and
longer focal lengths are the norm. In
these situations, the photographer is
still required to choose the required
autofocus frame or select a subject
using the manual focus function. The
photographer‘s aim here is to create
a powerful, unique image. Any small
deviations in the focal plane could
potentially diminish the technical
achievement of the image or even
completely alter the impact of the
photo, whether deliberately or not.
Advantages of AF systems
Autofocus systems have undergone
major developments since they were
first introduced in cameras in the
1980s. Manufacturers have steadily
improved their systems‘ performance
and efficiency in daily use, and
the combination of an increasing
number of AF points in the camera
bodies and ultrasonic motors in
the lenses has facilitated fast and
smooth focusing for the phase AF
systems typically found in today‘s SLR
cameras. For some applications, it is
precisely this speed that marks the
key benefit over other AF methods
such as the contrast-based AF
typically found in digital compact
cameras or manual focusing.
Good AF systems can generally
achieve a very high number of
„hits“ in terms of the sharp images
they produce with long telephoto
lenses in situations such as taking
shots of cheetahs in the wild,
snapping celebrities from within a
pack of paparazzi or photographing
footballers on the playing field.
So is there any place left
for manual focusing?
For any subject that is either not
actively moving away from the
photographer‘s position or that is set
to move into the “trap focus” after
careful pre-focusing, better results
can be achieved with careful manual
focusing. Carefully framed landscape
shots, images of buildings or
architectural details and meticulously
arranged tabletop displays in a
photographer‘s studio are unlikely to
require the use of autofocus.
Equally, both spontaneous portraits
and reportage shots can achieve the
same focusing precision by manual
means as by using an AF system.
Macro shots of butterflies on a
flower that require a very shallow
depth of field – where a tripod is
generally a sensible choice – should
always be precisely focused using
manual methods. In these cases,
it is rare for any of the camera‘s
AF points to coincide exactly with
the photographer‘s choice of focal
point and, all too frequently, the
focusing point covers too much of
the subject with a large extension
of depth, which means that it is no
longer possible to use the automatic
mechanism to achieve precise focus.
Were older cameras and
lenses actually better?
Anyone who has attempted to
manually focus modern AF SLR
cameras and their corresponding
AF lenses will have quickly come
to the sobering conclusion that,
practically speaking, this is far from
easy. Steep-pitch helical mounts,
play and backlash in the focus rings
of the lenses, dim viewfinders and
Photographer Michael Ankenbrand
Carl Zeiss July 2009 Page 8
Camera Lens News No 32
far-from-suitable screens in the
cameras make it very difficult to
achieve high-precision focusing. In
contrast, it is quite a revelation to go
back to one of the good SLR cameras
with a suitable lens from the era
before the widespread introduction
of AF systems and witness the large,
bright viewfinder, the eminently
practical adjustment aids on the
screen and the way in which a
subject seems to „spring to life“
when it is correctly in focus.
Few of today‘s cameras achieve
the innate viewfinder quality of
these analog models that have now
entered into the annals of history.
Nevertheless, some good digital
camera models from the medium
to top-class brackets, especially
full-frame cameras, do offer some
advantages for high-precision
manual focusing, at least thanks
to the glass prism in the viewfinder
and corresponding viewfinder
magnification.
What is the difference between
AF and MF lenses?
In terms of how lenses handle
manual focusing, even good-quality
AF lenses cannot offer the level of
precision of a simple manual focus
lens. The micro-motor in the lens
or in the camera requires a small
rotation angle and extremely smooth
action if it is to have any chance of
turning the focus ring and setting
the focus rapidly and quietly. This
is one instance where speed takes
precedence over accuracy! It is
therefore hardly surprising that cine
lenses for the Hollywood film industry
are focused manually and have no
autofocus option. If the lens has to
be operated remotely during filming
due to the camera being mounted in
an inaccessible spot, powerful servo
motors engage with the outermost
toothed rings of the lens. These are
powerful enough to precisely rotate
the focus ring with extraordinary
smoothness.
Manual photographic lenses
Nowadays, almost all manufacturers
only offer AF interchangeable lenses
and some systems – such as the
Canon EOS system – have never
even featured manual lenses at all
(apart from a few specialist models).
The current range of Carl Zeiss SLR
lenses incorporates some of the
expertise we have acquired from
our professional cine lenses. With
large rotation angles (e.g. almost
3�0 degrees in the case of the
Makro-Planar T* 2/100 from infinity
to the close-up limit of 0.44 m), a
Photographer Tobias Zehnder
On the set of Tom Tykwer‘s ‚The Perfume‘.
Carl Zeiss July 2009 Page 9
Camera Lens News No 32
wealth of available settings for
the all-metal unit and none of the
constraints caused by the need
to turn a focus motor, these lenses
achieve a level of focusing
accuracy that is far superior to any
conventional AF lenses. Thanks to
the popular range of lens mounts
comprising the ZF (Nikon F bayonet
mount), ZE (Canon EF bayonet
mount) and ZK (Pentax K bayonet
mount), the lenses can be directly
employed on suitable cameras at
high levels of functionality without
requiring an adapter.
AF cameras with MF lenses
This leads us to the question of how
far this accuracy can also be achieved
using modern (D)SLR cameras, most
of which suffer from the limitations
described above in comparison
to „old“ models without AF. The
focusing screens fitted as standard
to modern autofocus cameras are
primarily designed for a bright,
crystal-clear viewfinder. What they
generally lack, however, are optical
focusing aids (e.g. split image
rangefinder and microprisms) and
– due to their surface structure – the
ability to make any viable distinction
between „in focus“ and „out of
focus“. In addition, AF focus points
and other markings that appear
either on a second screen positioned
above or on an LCD display can make
it hard for the eye to clearly check the
focus on a single plane of the screen.
Other types of screens
By replacing the focusing screen with
a variant that has been optimized
for manual focus, it is possible to
achieve some major improvements.
This procedure can be carried out for
all SLR camera models, even if the
manufacturer claims otherwise and
fails to offer any interchangeable
focusing screens. For example,
Canon offers a choice between the
EC-A (with microprism ring) or EC-B
(with split image rangefinder) for
the models from its EOS-1 range.
Meanwhile, the EOS 5D and 5D MkII
have the option of the Ee-S screen,
though this does not feature any
focusing aids and therefore offers no
significant benefits over the screen
fitted as standard.
Both these lenses and smaller
models such as the Canon EOS 50D
and 40D, Nikon models up to the
D700 and DSLRs from Pentax and
Fuji can be fitted with excellent
focusing screens produced by other
manufacturers who offer variants
that have been specifically tailored to
each specific model. By following the
manufacturer‘s instructions and, in
some cases, using the supplied tool,
camera owners can carry out the
replacement of the screen themselves
without too much trouble as long as
the process is carried out carefully
in the most dust-free environment
available.
Replacement focusing screens
are available from the following
companies:
www.katzeyeoptics.com
www.photoproshop.com
www.intenscreen.com
http://haodascreen.com/Canon5D.
aspx
One problem, however, is that the
screen and/or the mirror are often
not perfectly aligned in many new
cameras, and it only takes a minimal
deviation (less than 1/100th to 1/10th
of a millimeter) to produce a visible
focus error (front focus or back
focus). As long as the user continues
to work with the AF system of the
camera and default focusing screen,
this minor error is generally not
conspicuous. However, if the screen
is replaced with a variant that
includes focusing aids, then the
deviation becomes visible.
Carl Zeiss July 2009 Page 10
Camera Lens News No 32
The only action that can be taken in
the face of this dilemma is to send
the camera to the manufacturer or an
authorized service center and request
that they align the screen properly.
For many camera models, aligning
the focusing screen involves inserting
or removing the corresponding
number of thin layers of film.
Electronic focusing aids:
fast, but not always perfect
In most of the Canon EOS, Nikon
AF and Pentax AF cameras, whether
digital or analog, electronic focus
confirmation continues to be
available even when using our ZE, ZF
or ZK lenses. The camera confirms
that the manual focus is correct by
illuminating the focus confirmation
light or the active AF point. In
many of the Nikon models (e.g.
the D700 and D3 series), additional
support is provided by two arrows
in the viewfinder which indicate the
direction of rotation for the focus
ring when performing fast manual
focusing.
However, these electronic focusing
aids only actually provide a relatively
imprecise means of achieving high-
precision manual focusing. The
region shown as „in focus“ when
rotating the focus ring is generally
quite large and is also dependent
on the direction from which the
subject is being brought into focus
(i.e. whether you are coming from
infinity or from the closest focus
distance). We therefore recommend
comprehensively testing the camera
in combination with a manual lens
in order to get a photographer‘s feel
for the situations in which you can
rely on the AF indicator. Especially
when using fast lenses, it is advisable
to take a bracketing series with
a wide-open aperture and short
shooting distances in order to achieve
optimum results.
It is sometimes possible to fall wide
of the mark when taking shots
with the aid of the focus confirmation
function, but fortunately some
recent camera models (e.g. the
Nikon D300, D700, D3 series and
the Canon EOS 5D MkII) have
incorporated an AF fine-tuning option
in the menu which obviously also
takes effect on the focus indicator
during manual focusing. If the
AF indicator consistently gives an
incorrect response when a certain
type of lens is used or even with
all lenses, then the focus error can
generally be rectified by carrying out
meticulous checks and adjustments.
Live View mode
Many of the latest DSLR cameras
enable a live image to be viewed on
the display prior to taking the shot.
It is usually possible to zoom into
this view far enough to carry out
focusing with great precision. Since
the camera‘s mirror has to be locked
up in this mode, the AF function
is either no longer available or the
mirror has to be briefly flipped down
and then back up again to carry out
focusing, depending on the specific
camera system. A further option is
the rather cumbersome contrast-
based autofocus function used in
compact cameras.
With the camera mounted on a
tripod and zoomed into the Live
View, a high-precision MF lens
enables accurate focusing. In addition,
Live View generally provides a bright,
crystal-clear image even in poor light.
Alignment tolerances of the focusing
screen, the mirror or the entire AF
system of the camera are no longer an
issue if Live View is used for manual
focusing. At least in those cameras
that take the preview image directly
from the image sensor, you see the
allocation of the focus exactly as it
will subsequently appear in the shot.
Carl Zeiss July 2009 Page 11
Camera Lens News No 32
Focus shift
Yet even with a perfectly aligned
focusing screen with focusing aids,
autofocus that is cleanly aligned
or adjusted using the camera‘s
menu and the Live View function,
it is impossible to guarantee proper
checking of the focus prior to
shooting in every single case.
Spherical aberration in lenses leads
to so-called focus shifts. This term
refers to the fact that changing
the aperture causes a shift in the
optimum focus position. This effect
is particularly conspicuous in the case
of fast prime lenses. You can find a
more detailed description of focus
shift in the article „Measuring lenses
objectively“ which appears in Camera
Lens News Nr. 30 starting on page 24.
In order to take into account the
effect of focus shift on precise
focusing, the user should – as far as
possible – carry out focusing at the
aperture at which the shot is sub-
sequently to be taken. Nevertheless,
there are still a number of limitations
to be considered: AF systems in
current camera models do not take
into account the focus shift of the
lens. This means that the reliability
of the AF indicator varies depending
on the type of lens, f-stops and
shooting distances.
Due to their surface structure,
focusing screens in fast lenses are
not capable of factoring in all the
incoming rays. This can easily be seen
from the fact that – depending on
the design – the brightness of the
focusing screen no longer changes
with lenses such as those that are
faster than 1:2.8. This means that
the change in the optimum focus
position can no longer be evaluated
on the focusing screen at wide
apertures when using very fast
lenses.
And there is also a “fly in the
ointment” when it comes to the use
of the Live View function, namely
the fact that many current camera
models (e.g. the Nikon D700 and the
Canon EOS 5D MkII) automatically
control the aperture in the Live View
mode based on the set ISO values
and the ambient light in order to
ensure that the image in the display
is consistently shown with the correct
brightness and contrast values. This
means that it is no longer possible
to close the aperture to the desired,
fixed setting using the preview
button. Correct evaluation of the
depth of field and focus position is
therefore equally out of reach using
this method, since the aperture is
only closed to the desired setting
when the shot is actually taken.
Conclusion
When your aim is to take
photographs with wide apertures and
extremely accurate focusing, high-
precision manual lenses can make
your work easier. Enhanced focusing
screens, a well-aligned AF system
and use of the Live View mode all
help to make focusing more precise.
Although the influence of focus shift
cannot be ignored, it can produce
better, reproducible results if suitable
care is taken. In situations where
focusing accuracy is of paramount
importance, it is also advisable
to take finely graded bracketing
sequences.
Carl Zeiss July 2009 Page 12
Camera Lens News No 32
The Carl Zeiss Distagon T* 2,8/21 has
given us the confidence we need to
take truly uncompromising shots with
a wide-open aperture.
A reliable wide-angle lens is an
absolute must when you are trying to
capture the hectic street life of New
York. It paves the way for capturing
the city’s atmosphere together with
its sophisticated architecture – that
very special combination that makes
the metropolis of New York City so
very unique.
New York City Impressions With the Distagon T* 2,8/21
We primarily used the
Distagon T* 2,8/21 to shoot highly
contrasting street scenes at night
under tricky lighting conditions.
Once again, we achieved some
stunning results. Focusing was smooth
and consistent and it made it
absolutely clear that the composition
Carl Zeiss July 2009 Page 13
Camera Lens News No 32
Camera Lens News
A newsletter for all who use, buy, sell, like,
report about and are interested in Carl Zeiss
camera lenses.
All information in Camera Lens News is
accurate to the best of our knowledge at
the time of publication.
Publisher:
Carl Zeiss AG
Camera Lens Division
Marketing
7344� Oberkochen
Germany
Phone: +49 (0) 73�4/ 20-�175
Email: photo@zeiss.de
Internet: www.zeiss.de/photo
Shoot Studio The combined
talents of Shoot Studio‘s four
photographers, Jean-François
Gratton, Pierre Manning, Martin
Girard and Jean-François Lemire
deliver powerful advertising,
cultural, corporate and editorial
photography. Supported by
an outstanding team, Shoot
Studio unites a prolific group of
artists who strive to discover the
unexplored through technology
and personal development.
of the image was entirely in our
own hands.
In addition to the street shots, we
also tested out the macro capabilities
of the lens using this cutlery basket.
The meticulous precision of the
Distagon T* 2,8/21 really came to
the fore here, allowing us to bring
subjects very close to the lens.