Voigtländer Nokton 17.5mm f0.95 MFT review

ON TRIAL
ON TRIAL
All the barrel markings are engraved
rather than screen-printed and
include a depth-of-field scale for
apertures between f4.0 and f16.
As the mount is passive, there is no interface with
the camera body so everything is done manually and
Panasonic cameras, in particular, have to be set to
‘Shoot Without Lens’ via their custom menus. Of course,
manual focusing and diaphragm control isn’t really
an issue when shooting video.
RIGHT: The focusing collar has the
traditional metal ribbed segments for
enhanced grip and is exceptionally
smooth in its action, allowing for very
precise focus adjustments.
elements are all glass (plus the mount is stainless
steel). It’s made in Japan by Cosina which owns
the rights to the Voigtländer name, and also builds
lenses for a number of other equally famous
brands via OEM arrangements that are closelyguarded secrets.
Apart from the sheer solidity of the way it feels
in the hand, the Voigtländer also has the same
precision of operation and finish as you’d expect
of either Leica or Zeiss. The focusing collar is silky
smooth in its action – and consistently so across
the distance range – while the control itself harks
back to the classic designs of the 1950s and ’60s so
it doesn’t even use rubberised inserts to enhance
grip and instead is entirely metal with ribbed sections at intervals.
BELOW: As is now expected of Cosina’s Voigtländer lenses, the 17.5mm
f0.95 is beautifully finished and boasts a build quality comparable to
that of either Leica or Zeiss.
Smooth Operator
Open
Wider
VOIGTLÄNDER NOKTON
17.5MM F0.95 MFT
Cosina has followed up its super-fast fifty for the Micro Four Thirds
format with another f0.95 Voigtländer Nokton prime lens… this time
with the added appeal of being a wide-angle. Report by Paul Burrows.
I
f you’re still tossing up which compact system
camera (CSC) format to adopt, the ever-widening
choice of lenses available for the Micro Four
Thirds models has to be an important consideration. Apart from the highly active lens programs
of both Olympus and Panasonic – the former, in
particular, introducing some superb classicallystyled primes – there are contributions from Sigma,
Tamron, Voigtländer and, soon, Zeiss. Among the
new mount systems, MFT is undoubtedly the best
served for lenses from ultra-modern, ultra-compact
powered zooms to ‘old school’ glass such as
Voigtländer’s latest ultra-fast Nokton.
The 17.5mm f0.95 model follows the earlier
25mm, giving the choice of a standard 35mm
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wide-angle as an alternative to the classic ‘fast
fifty’ (MFT’s focal length magnification factor being
1.97x). It is very much the antithesis of the compact
zooms and pancake primes that are currently in
vogue for the CSCs; being big, heavy and virtually entirely free of any plastics in its construction.
That said, it doesn’t seem at all out of place on
Panasonic’s SLR-style Lumix bodies – especially
the big-is-better GH3 – nor on Olympus’s E-M5
whose OM-inspired styling nicely compliments
the Voigtländer’s traditional control collars and
engraved markings.
At over half a kilogram, the 17.5mm f0.95 is
a weighty beast by today’s standards, but that’s
because the barrel tubes are all metal and the lens
Fully manual control is the name of the game with
the 17.5mm Nokton as the lens mount is purely
mechanical so there’s no electronic interface with
the camera body. This means that, in addition to
manual focusing, aperture control is fully manual
too, using either the aperture-priority auto or
manual exposure modes.
In the case of Panasonic’s Lumix G-series
camera bodies, it’s also necessary to select
‘Shoot Without Lens’ before they’ll work with the
Voigtländer lens while, in all cases, no lens-related
details (i.e. either the shooting aperture or the focal
length) is recorded in the Exif data. Additionally, any
in-camera correction for lens aberrations won’t be
available either, but at-capture image processing for
things such as dynamic range or the application of
special effects remain unchanged.
However, the 17.5mm isn’t entirely back in the
1950s, because the aperture control collar can be
switched between click-stopped operation (in halfstop increments) or continuous adjustment. This is
done by pulling an adjacent control ring towards
the lens mount and then turning it through 180
degrees. Why might you want continuous adjustment of the diaphragm? When shooting video, of
course, which is when the super-smooth manual
focusing control also comes into its own.
And bear in mind that f0.95 to f16 in half-stop
steps is a total of 16 clicks so being able to sweep
through the range in one action is much quicker.
No click-stops also means no noise and, of course,
the manual focusing is as quiet as you make it. So
you can see at a glance which mode is engaged,
the index mark is either white (click-stopped) or
yellow (continuous).
On The Inside
While it may be all classical styling and traditional
construction methods on the outside, the 17.5mm
Nokton is very much 21st century on the inside with
“While it may be all classical styling and traditional
construction methods on the outside, the 17.5mm
Nokton is very much 21st century on the inside with
its glass formulations optimised for digital capture.”
its glass formulations optimised for digital capture
and specific measures such as beefed up antireflection coatings.
The optical construction comprises 13 elements
in nine groups with one aspherical type and one
made from optical glass with a high refractive index
to counter distortion and chromatic aberrations
respectively. The minimum focusing distance is 15
centimetres which gives a maximum magnification ratio of 1:4 or one-quarter lifesize… certainly
not into the macro range, but handy nonetheless.
The front element doesn’t rotate during focusing
so orientation-sensitive filters aren’t affected. The
screwthread filter fitting is 58 mm in diameter. As
with the 25mm version, the 17.5mm has a tenbladed diaphragm which generates nicely rounded,
smooth out-of-focus effects.
Even on a smaller-than-35mm format like Micro
Four Thirds, f0.95 still represents extremely shallow
depth-of-field so the precision of the focusing ring
is important. It actually rotates through nearly 200
degrees so it can be stopped on a sliver of subject
matter and then very finely adjusted as required.
Depending on the MFT camera body, the magnified live view image for assisting with focus may or
may not be available in which case you’re going to
be relying entirely on either the EVF or the moni-
tor screen which is where more resolution will be
helpful. So, for example, the Lumix GH3 generates a
magnified image, but it has to be manually activated
and then there’s the option of having a selected
enlarged section (within the normal image) which
can be moved around the frame as required, or the
entire screen can be filled and positioning is guided
by a graphic.
Conveniently, MF assist can be assigned to
a function button so it’s always easily accessed
when the 17.5mm Nokton is in use. At 10x enlargement, precisely focusing the lens is a breeze and,
of course, the GH3 provides the choice of both EVF
and external monitor screen.
The lens’s distance scale is marked in both feet
and metres, and there’s a depth-of-field scale with
markings for f4.0, f5.6, f8.0, f11 and f16.
Performance
You’re not going to be surprised to learn that the
f0.95 aperture setting comes with some compromises in terms of image sharpness and brightness.
Both fall off markedly towards the corners of the
frame – more than with the 25mm lens – but the
loss of sharpness at the corners may be less of
an issue in some circumstances as the extremely
shallow depth-of-field has already rendered the
foreground and background out of focus anyway.
That said, the degree of sharpness at the centre
of the frame is still impressive given the combination of focal length and aperture. Vignetting is quite
pronounced at f0.95, with the light fall-off being as
much as two stops.
Stopping down – even just to f1.4 – works miracles in terms of the centre-to-corner uniformity of
both the sharpness and the vignetting. The former
is optimised at f5.6 and the latter is entirely eliminated at f2.8. Being an apochromatic design, the
17.5mm Nokton does a reasonable job of supressing chromatic aberrations, but inevitably some
colour fringing on high contrast edges is evident
in big enlargements of images captured at f0.95.
It’s significantly reduced between f2.8 and f11.
Spherical aberration is also noticeable when
shooting wide-open – most obviously with points
of light – but it’s slight and unlikely to be
particularly troublesome.
Some slight barrel-type distortion is also present, but only really apparent when straight lines
in the image are positioned very close to the
frame edges. Post-camera correction proves to be
pretty effective. Both flare and ghosting are well
supressed, but fitting the supplied metal hood is
essential. Handily, a cap for the hood is supplied as
45
ON TRIAL
well as one for the lens so you can leave the shade
fitted without worrying about dust. There’s a slight
loss of contrast when shooting wide-open, but it’s
easily corrected by bumping up the contrast incamera for JPEGs or post-camera for RAWs.
All the points made here about performance
are endemic with ultra-fast lenses, but the bottom
line is that the 17.5mm f0.95 Nokton is still pretty
impressive in all departments, especially in the light
of its price tag. You’d pay many, many times more
for something comparable badged either Leica
or Zeiss, but in truth the Voigtländer lens is pretty
much on a par in terms of both its construction
quality and its optical quality (taking into account, of
course, differences in format).
The stepless aperture control is hugely appealing if shooting video is your bag, as are the creative
focus effects achievable courtesy of the super-
Voigtländer Nokton
17.5mm f0.95 MFT
$1095
Format: Micro Four Thirds.
Focal Length: 35mm on MFT compact
system cameras.
Angle-of-View: 64.6 degrees (diagonal).
Construction: 13 elements/9 groups.
Minimum Focus: 15 cm.
Maximum Reproduction Ratio: 1:4.
Aperture Range: f0.95 – f16.
Overall Length: 80.0 mm.
Maximum Diameter: 63.4 mm.
Filter Diameter: 58 mm.
Weight: 540 grams.
Lens Mount(s):
Micro Four Thirds System.
Features: All-metal barrel
construction (including grip), all-glass optical construction, depth-of-field scale, full multi-coating,
switchable aperture control control between continuous and click-stops, ten-bladed diaphragm.
Metal lens hood supplied with its own cap.
Price: $1095.
Distributor: Mainline Photographics Pty Ltd,
telephone (02) 9437 5800 or visit
www.mainlinephoto.com.au
“Stopping down
– even just to f1.4 –
works miracles in terms
of the centre-to-corner
uniformity of both the
sharpness and
the vignetting.”
shallow depth-of-field at f0.95. It’s worth noting that
video-makers won’t be at all phased by an entirely
manual lens… many expert shooters find it much
more desirable in terms of enhanced creative control over key visual effects. Of course, depth-of-field
aside, being able to shoot at f0.95 provides a means
of dealing with low light situations without cranking
up the sensitivity to very high ISO levels.
The Verdict
We still marvel at how Cosina manages to actually
achieve what it does with its Voigtländer-branded
lenses – for any format or mount – and still charge
what it does. At a whisker under $1100, this lens
is still pretty good value for money given its
overall performance.
The Nokton 17.5mm f0.95 is the fastest wideangle available for the Micro Four Thirds cameras
and it isn’t likely to be challenged for this title in
the near future. It’s also unlikely to be challenged in
terms of its exceptional build quality and its styling
which doesn’t just look traditional, it really is. Even
the classiest M.Zuiko Digital primes from Olympus
aren’t quite in the same league.
Of course, there are other 35mm focal length
(equivalent) primes for MFT cameras which can
provide the convenience of autofocusing and auto
exposure control, but they can’t match the experience of using the Voigtländer, its low-light capabilities or the creative possibilities inherent in being
able to shoot at f0.95.
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Given the inherent
optical challenges,
the Voigtländer
17.5mm performs well at full
aperture, although
there is fall-off in
both sharpness and
brightness towards
the corners of the
frame. Stopping
down – even just
to f1.4 – improves
the centre-to-edge
consistency of both
quite markedly.