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If 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 consid-

eration. Apart from the highly active lens programs of both Olympus and Panasonic – the former, in particular, introducing some superb classically-styled 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

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 virtu-ally 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

Cosina has followed up its super-fast fi fty 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.

its glass formulations optimised for digital capture and specific measures such as beefed up anti-reflection 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 magnifica-tion 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 ten-bladed 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 magni-fied 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 enlarge-ment, 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.

PerformanceYou’re not going to be surprised to learn that the f0.95 aperture setting comes with some compro-mises 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 combina-tion 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 mir-acles 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 elimi-nated at f2.8. Being an apochromatic design, the 17.5mm Nokton does a reasonable job of supress-ing 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 pres-ent, 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

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 closely-guarded 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 sec-tions at intervals.

Smooth OperatorFully 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 half-stop 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 adjust-ment 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 InsideWhile 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

VOIGTLÄNDER NOKTON 17.5MM F0.95 MFT

“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.”

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.

Open Wider

BELOW: As is now expected of Cosina’s Voigtländer lenses, the 17.5mm f0.95 is beautifully fi nished and boasts a build quality comparable to that of either Leica or Zeiss.

All the barrel markings are engraved rather than screen-printed and include a depth-of-fi eld scale for apertures between f4.0 and f16.

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.

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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 in-camera 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 appeal-ing if shooting video is your bag, as are the creative focus effects achievable courtesy of the super-

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 con-trol 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 VerdictWe 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 wide-angle 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 experi-ence of using the Voigtländer, its low-light capabili-ties or the creative possibilities inherent in being able to shoot at f0.95.

“Stopping down – even just to f1.4 – works miracles in terms of the centre-to-corner uniformity of both the sharpness and the vignetting.”

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 con-struction, depth-of-fi eld scale, full multi-coating, switchable aperture control control between con-tinuous 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

Voigtländer Nokton 17.5mm f0.95 MFT $1095

Micro Four Thirds System. All-metal barrel

Given the inherent optical challenges, the Voigtländer 17.5mm per-forms 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.