Into the Big Wide Open

TECHNOLOGY HCD 4/28

INTO THE BIG WIDE OPEN

BY HANNS W. FRIEDRICH The new HCD 4/28 lens in the H series represents Hasselblad’s long- construction of a lens, no matter how PHOTO: JÜRGEN MÜLLER scrupulously designed. All HC lenses awaited entry into extreme wide-angle photography. This lens – a utilize DAC, but the HCD 4/28 is the digital exclusive – was designed with certain digital processes in mind, first Hasselblad lens to rely on DAC for outstanding picture quality. leading the company through unknown technical territory. For the time being, the digital auto correction resolves two – soon three – typical optical aberrations. The tiny gap that once existed in 28mm owes its compactness. ‘D’ minimum chromatic aberration and The first DAC level has long estab- the selection of wide-angle lenses in stands for digital and signifies that maximum resolution. Any distor- lished a footing in the image Hasselblad’s H system has now been it works with digital Hasselblad cam- tion was to be corrected digitally. formation sequence and stands for filled. Mounted on a film body, the eras only – the new H3D models to be Had the priority been lowest pos- ‘Digital Apo Correction’. It elimi- existing HC 3.5/35 will yield an exact. Since most photographers will sible distortion, the lens would have nates residual chromatic aberrations expansive 89-degree angle of view have converted to digital by now, turned out substantially more com- induced by optical constraints that – enough to capture anything from the fact that the 28mm is designed plex; bulkier, heavier and pricier. It cannot be avoided, regardless of how vast scenic views to extreme close- exclusively for digital operation is would have altered the nature of the zero-tolerance oriented the HC lens up portraiture with exaggerated less restricting than in recent years. lens design process. The result – the designs are. DAC practically eradi- proportions. The digital H3D series, In the end, it is this restriction that HCD 4/28 with DAC implemented cates the residual purple fringing, however, is affected by a lens factor raises the photographic reproduc- from the start – is probably a better occasionally caused by chromatic that alters the perspective of a focal tion as a whole to a higher level. Per lens than a hypothetical, DAC-less aberration. The second, recently length both when compared to film Nordlund talks about this in a com- 28mm could ever be. introduced level of the digital auto and 48mm ‘full format’. The digital prehensive interview on page 42. correction system counteracts the H3D-22 and -39 – which hold the The 28mm is so wonderfully com- DIGITAL DISTORTION described inherent distortion of HC full-format title – do in fact yield a pact precisely because of its limited CORRECTION lenses. The same principle applies: lens factor of 1.1; and while mod- compatibility, as it focuses only on almost any lens will distort if the erate, it will transform the 35mm the smaller image circle of digital 2 It is worth pointing out that the conditions are right, causing straight mentioned above into a hypotheti- sensors. While the 49.1 x 37 mil- distortion factor is the HCD 4/28’s lines in the viewfinder periphery to cal ‘38.5mm' lens. But 38 millimeters limeter size of the sensor (H3D-22 only ‘weakness’. In all other disci- warp. However, all HC lenses are fall short of the extreme 90 degree, and -39) is not much smaller than plines of photography – when it designed to keep distortion to an or more, angle of view necessary in the 56 by 42 millimeters of the film comes to the chromatic aberration absolute minimum, even without order to qualify for ‘the big wide frame correcting a 28mm lens for the or refining the reproduction in close the interference of corrective soft- open’. The marginally smaller sen- entire medium format film plane – in range, for example – the lens is just ware. Only the HCD 4/28 finds itself sor of the brand-new H3D-31, by spite of what appears to be a negli- as good, if not better than those HC slightly below what is commonly comparison, has a lens factor of 1.3 gible difference in size – demands a lenses that are already prized for accepted by professionals – for this and is therefore affected similarly. substantially larger lens shell, along their capacity to deliver immaculate reason, DAC plays a crucial part in The newly introduced HCD 4/28 with wider, more expensive glass dia- results on film. According to Has- the design process. serves to fill that last gap in the lens meters. This is the reason why Hassel- selblad, the HCD 4/28 really only Hasselblad intends to launch a gamut. Mounted on an H3D-22 or blad decided to build a lens for digital distorts slightly more than the HC third level of correction: DAC III will -39, the 28mm opens up to a superb sensors only, making the HCD 4/28 3.5/35 and is still within acceptable deal with vignetting, i.e., declining 95-degree angle of view. In 35mm ter- the first to be designed specifically for limits. Those who persist will find a brightness towards the corners of the minology this would correspond to a the 48mm full format. Mounted on subtle bend in the viewfinder periph- image. While chromatic aberration 20mm lens. The H system now meas- an analogue body would only result ery, where otherwise straight lines and distortion are never welcome, sures up to digital 35mm cameras in in a reduction of brightness in the take on a moderately barrel-shaped vignetting is a frequently accepted, one of the most important arenas of image periphery. Digitally, however, distortion; but this will not affect the occasionally even desirable photo- photography: the wide-angle zone. the 28mm will fully illuminate the composition in any way. graphic ‘error’. So Hasselblad plans The new HCD 4/28 safeguards excep- smaller image circle of the sensor. Hasselblad moves on to perfect the to include a slider for the adjustment tional picture quality, zero distortion Once it had been established that picture with software, starting with of vignetting, allowing the photogra- and crisp detail throughout the full the new 28mm lens was to be a digi- an automated removal of distortion. pher to fully eradicate the peripheral image plane – at every range. tal exclusive, Hasselblad took it one This happens without the photo- reduction in brightness or, if desired, The new HCD 4/28 beckons step further, bumping up the lens grapher ever noticing and is free of enhance it. While this FlexColor owners of H3D cameras into SMALL, SOLID, design with a few digital tweaks and, side effects, as the Digital Auto Cor- feature awaits to be integrated, all the realm of extreme wide- AFFORDABLE in doing so, exploiting the potential rection (DAC) is an integral element HC lenses – including the HCD 4/28 angle photography, offering of the digital medium. Fully aware of the FlexColor software, which he – yield very little vignetting as it is, an enormous angle of view 1 The HCD 4/28 is small, solid and that it would need DAC to counteract uses to manipulate the picture after even without DAC. DAC is only ever of 95 degrees – without being affordable all at once. To some this a slightly greater lens distortion than the exposure. The digital auto correc- responsible for that last drop of qual- as big a build as it may seem may come as a surprise. “HCD” hints usual, the team of engineers decided tion removes those very last optical ity, turning an already great picture in this picture at the technical trick to which the to make it their priority to achieve aberrations that are inherent in the into an immaculate one.

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222364_VIC02_E_T_Lens28.indd2364_VIC02_E_T_Lens28.indd 3939 004.04.20074.04.2007 15:56:1015:56:10 UUhrhr TECHNOLOGY HCD 4/28

HCD 4/28 – AT A GLANCE Hasselblad’s HCD 4/28 is born from or -39, however, the angle of view Indoors, the short focal length of a pragmatic approach. Surely they expands perceptibly. This is where the HCD 4/28 can create a feeling LENS DESIGN 1 could have developed a 28mm lens the new HCD 4/28 lens really comes of depth. The lens reproduces de- capable of dealing with the larger into its own. tail homogenously from the center The optical design of image circle of film; indeed, all From an outsider’s point of view, to the corners of the picture the HCD 4/28 is based on the HC 3.5/35 und consists optical characteristics could have it could look as though Hasselblad’s of 12 lenses in 9 groups. been carried through within satisfac- developers were trying to circum- The fact that a slightly tory parameters – even without the vent the blemishes of their lenses higher distortion was ac- digital boost. Having said that, the by patching them up with digital cepted (which can easily vast majority of H camera owners has band-aids. This couldn’t be further be removed digitally) has jumped onto the digital bandwagon from the truth. The choice to embark resulted in an unusually and would no longer appreciate the upon technologically unfamiliar compact design for this effort it would take to concoct such territory was a conscious one. The super-wide angle lens a design. An alternative could have promise of a fully integrated digi- been a large and heavy lens with a tal camera system, in which the bulging front element, a proud price numerous components – from lens 2 DIGITAL DISTORTION CORRECTION tag and still no absolute, aberration- via camera to digital back – are pro- free guarantee. vided by one company, is now being exploited for the first time ever. The WIDE-ANGLE approach is unprecedented amongst PHOTOGRAPHY digital system cameras, even outside WITH THE H3D-31 of medium format. All resources were utilized to generate the best picture Hasselblad were probably thinking possible. In the end, the images fea- of H3D-31 owners when the 28mm tured in this spread will abolish any was designed, as it overcomes the lingering doubt in the HCD 4/28’s obstacle of the smaller sensor with a ability to lay down a stunning result. bona fide wide-angle. In relation to What’s truly great about the HCD the larger sensors of the other H3D 4/28 is that it allows you to forget models, the H3D-31 yields a 1.2 lens the technological effort that went factor, or, in relation to film, a 1.3 into its development, facilitating the By allowing the HCD 4/28 a distance settings. When uncor- lens factor. The 28mm lens therefore same natural and creative handling slightly higher distortion, Hassel- rected, the distortion of the lens has a focal length the equivalent of as all other HC lenses. Its expansive blad was able to concentrate is visible (left), but this effect is a 36mm lens with an angle of view angle of view will capture the vast- on the correction of chromatic totally removed by the Digital measuring 89 degrees. This way, ness of a lush landscape and also aberrations and excellent detail Auto Correction integrated in the purchasers of an H3D-31 also have provide a generous perspective in reproduction up to the shortest FlexColor software (right) the chance to dabble in wide-angle architectural photography. Indoors photography. Mounted on a H3D-22 it will enable you to expose a broad

Thanks to Digital Auto Correction view in a very tight space. The lens’s (DAC) the HCD 4/28 keeps dis- optical performance remains excel- tortion to a minimum, generating lent at close range and enables you to crisp detail at every range (left) exaggerate the perspective of an ob- ject placed only 10 centimeters from the front lens element – no extension tubes needed. In other words: the HCD 4/28 finally takes the H system into extreme wide-angle dimensions, producing the excellent reproduction qualities of the H3D models in a photographic discipline that, once Photos: Jürgen Holzenleuchter upon a time, obliged turning to far Location: Hotel Ku’Damm 101, Berlin inferior camera systems. www.kudamm101.com

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222364_VIC02_E_T_Lens28.indd2364_VIC02_E_T_Lens28.indd 4040 004.04.20074.04.2007 15:56:1815:56:18 UUhrhr 222364_VIC02_E_T_Lens28.indd2364_VIC02_E_T_Lens28.indd 4141 004.04.20074.04.2007 15:56:3015:56:30 UUhrhr