New Leica S2 and new lenses



On Monday September 22, at around 1930 (CET), Dr Kaufmann, CEO of Leica, introduced a new camera system made by Leica, the Pro format Leica S2. While he spoke, laptops were connected to the internet and the news was all over the world in hours. The basics are already well known: a 30x45mm sized sensor with 37.5 Mp in a body, closely resembling the shape and size of the R8/9. The sensor has the classical 2:3 shape of the Barnack format and is 60% bigger than the classical 35mm format. The body has a focal plane shutter with speeds up to 1/4000 and has a newly developed AF system. The claims for speed and sound are ambitious and we have to wait for true production models to substantiate them. Four lenses have been announced at the start, three of them with apertures of 1:2.5 and one with an aperture of 3.5.
Leica S-System


The wide apertures of the lenses and the use of the classical slr shape and viewfinder system are a direct challenge to Hasselblad and Mamiya and with almost 40 Mp the system is also meant to attract users of the digital back studio cameras. Closely following the Leica rule of small size and high performance and intuitive handling, the S2 should bring documentary style photography into the studio and improve on the somewhat slow and cumbersome handling of most studio cameras. The cooperation with Phase One indicates that this company believes that the very conservative clientele of the digital medium format domain can be persuaded to go the Leica way.

The camera body, interesting as this is, does not show truly remarkable features. The lenses on the other hand are very innovative. The high speed of 2.5 is a direct poke in the eye of the classical Hasselblad lens system that starts at 2.8. The medium format lenses are generally weak in the close range performance and the contrast at finer detail definition. The new Leica CS lens line offers excellent image quality at close range and have very high MTF values at 60 lp/mm, sometimes even better than what you get with the current M-lenses. When you combine the lens quality with the sensor size and pixel count, you may expect superior performance. One of the reasons for this performance is the design of the new all metal central leaf shutter, which offers a top speed of at least 1/500, possibly more. The shutter has some very innovative features in speed of opening and closing of the blades. Most important is the diameter: all existing shutters have a relatively wide outer diameter and a smaller inner diameter. The result is a lens with a big mount and a narrow passage for the light through the lens. Leica designed a new shutter with small outer and wide inner diameters. The 120 and the 180 lenses find their roots in the superb R-lenses Apo-Macro-Elmarit 100 and Apo_Elmarit-R 2.8/180, the 70 and 35 lenses are entirely new.

Some background


The Africa/Afrika project (Auto Focus Reflex Camera) was initiated by S. Lee immediately after Photokina 2006. Lee believed that a new DSLR was required for Leica to be assured of continued professional interest and claim the attention of the enthusiast Leica users. The CRF system is very important, but it would be too narrow a base to sustain the growth of the company. But the competition by the top products of the Japanese manufacturers is quite heavy and their pace of introduction of new features and improvements is too high for Leica to follow. And the technological end engineering experience within the Leica company for high end dSLR products needs to be expanded in breadth and depth. You cannot make yourself too dependent on outside sources. So Lee preferred to evade for the time being the direct confrontation with the Japanese 24x36mm sensor sized products and tried to profile the Leica camera company in a new market where innovative pace is slower and the professional image is worth more and price not the issue. Here Leica can exploit its best values without being forced to act on the inflation of features and the price erosion of high end consumer/professional dslr products in that hotly contested market.
It is a remarkable and bold move to go up-market where everybody assumes that downsizing is the best option for survival.
Dr. Kaufmann stressed the fact that Leica engineering teams are working under full pressure to finish the R10, but did not mention when or what we can expect this new model. But he stressed also the fact that the know-how of the Africa project would be of utmost value for the new DSLR products. The basic approach is to define and create products that show the Leica DNA and are not a me-too product that in essence is a pale shadow of the main contenders in the market. Nikon, Canon and now Sony are engaged in a fierce battle for the market share with almost identical products. All three have deep pockets and can allow themselves to introduce new products every year.
Leica needs another approach: durable and basic features allow for a longer product life, but require a more thorough thinking and reflection on the essence of photographic qualities.The S2 is a big gamble for Leica, but a most necessary step to evolve and expand into a prominent player in the digital high end market.
Some knowns are still unknown and some unknowns wait to become known.

Leica S2: its significance (august 9, 2009)



The original intention for the development of the Leica S2 was twofold: (1) to demonstrate that Leica could be profiled as a leader and major player in the digital imaging field (Technologieträger = platform for advanced technology) and to use the insights for a spin off into a new range of products. (2) to shift the focus for new digital products into a market that is less hotly contended than the high end slr segment.
Leica's dalliance with medium format camera technology has a longer history. A number of years ago, the management was contemplating a takeover of Hasselblad. Several years later an attempt to buy Sinar was not successful and very recently a deal with Phase One was cancelled. Now the takeover of Sinar succeeded (2014)

The attractiveness of the medium format market lies in a combination of factors: it is a market with only a handful of players where you can profile yourself as a premium brand, it is a market with a relatively low level of competition and interesting profit margins, it is a market with a slow product renewal and a high customer loyalty. After assessing Leica's strengths and weaknesses, Steven Lee rightly concluded that the Solms company is not fit for a prolonged fight in the highly competitive dslr market with aggressive players like Canon and Nikon. One could say that Leica is a too polite company to operate in this arena.

The current state of affairs in the medium format market favors some of the strengths of the Leica profile: a high quality low volume production, a customer base that is accustomed to a very high price level and at the same time demanding superior quality. This market is dominated by the stationary studio-based cameras and lacking is a product that allows for dynamic reportage-like photography. This is precisely the domain where Leica's fame has been made. But the transfer of the Leica rangefinder philosophy into a medium format single lens reflex is a major challenge that is historically not very successful. The Mamiya ZD is dangling at the edge of the market and the Pentax version is now on the market.

Leica stresses the fact that the size and volume of the S2 are comparable with the footprint of a product like the Nikon D3. This is true, but the D3 is undeniably a big and heavy camera. The comparison with the Nikon signifies that the real competition for the Leica S2 is the high-end professional equipment of Canon and Nikon. If the current pace of development can be interpreted as a trend, then we may expect at Photokina 2010 the introduction of 30+ Megapixel cameras by Nikon and Canon.
True to tradition Leica has opted for a format ratio of 2:3 (the classical Barnack format). This choice might become a hindrance for professional acceptance in the medium format segment. Almost all manufacturers have chosen for a format (1:1, 4:3 or 5:4) tending to square. These ratios are close to the ideal format (56 x 72) as defined by Linhof long ago.

Barnack considered the 2:3 ratio as the best for aesthetic composition in pictures. The 1.5 ratio is closer to the so-called golden section or golden ratio, which is defined as "phi" or 1.618033988.…. than the Linhof ratio. But the use and effectiveness of the golden ratio have been greatly exaggerated and common paper sizes (and television screens) are more often in the 4:3 ratio.
The S2 format is the odd man out in the medium format segment. Can the S2 seduce the traditionally minded studio, fashion and product photographers and image makers by this combination of a different format, more tuned to reportage and handheld photography and a high quality sensor, coupled to potent optics?
And can the S2 redefine medium format photography as the original camera camera did in the thirties of the previous century. The assumption has been made that the original Leica format succeeded because it fitted into the Zeitgeist. A bigger sensor fits into the modern culture and therefore Leica could become the trailblazer of the concept of a bigger sensor in a body size that is associated with the much smaller size of the classical 35mm film.
The weight and volume of the current Nikon D3 and Canon 1Ds are in fact totally out of proportion. The sensor size dwarfs in comparison with the massive volume of the body that encloses it. There certainly is enough room inside the body to accommodate a bigger sensor. But then a range of new lenses is necessary. Even if the Japanese companies would incorporate an S2-sized sensor into the existing camera bodies, this would not benefit Leica at all. The situation now is totally different from the days when Barnack fitted the 24 x 36 size between the standard cine film sprocket holes.
The S2 shape is closely modeled on that of a Sumo wrestler: strong and solidly standing on its feet, radiating uncompromising power, but it lacks the nimbleness and elegance of a distant predecessor like the Leica IIIc.

It is often assumed that the Barnack revolution was based on image quality and format size. The early adopters of the Leica camera were artists, many of them standing in the surrealist culture. Important for them were the compactness of the camera, the fastness of its operation and the fact that you could operate the camera at eye level. These features allowed for the creation of the new vision, the photography style characterized by a flexible and spontaneous view of life. The Leica could be taken everywhere and was ready to take pictures at any time of the day.
Image quality was not the prime concern of these photographers. It was as it were a byproduct. Surrealists were searching for essence, not surface representation.

In one sense the Sumo-Leica could re-enact the revolutionary spirit of the Barnack era. It is the only camera in the big sensor league that allows for natural eye-level operation. Whether this is enough to start a new (digital) New Vision remains to be seen.

If leaked reports about the future plans of Nikon are to be believed, Leica has one year to develop a new style of high-end-big-sensor type of photography. This presupposes a massive and concentrated communication effort by Leica, a task the current marketing department would find it difficult to accomplish.

The S2 is slowly changing its DNA: at first the camera was presented as a Technologieträger: a laboratory to demonstrate Leica's prowess in digital technology, but more and more the S2 is becoming a Hoffnungsträger, a platform of hope and promise, in fact the pillar on which the future of Leica rests. The company would not do the S2 a favor in supporting this change in role and profile. The usual marketing speak that the S2 is the start of a whole family of products lacks substance.

The range of true Leica (Solms originated) products is rather narrow at this moment: the promised R10 vanished, the M line is increasingly relegated to a niche role with limited appeal and the rest of the Leica product line is of Japanese origin. In the recent company report we read that Leica is contemplating more cooperation with other companies to close gaps in the product range.

Leica's strategy for long term survival and growth seems to depend on a two-pronged approach: the creation of a broad range of products for mid and high end range for discerning consumers in cooperation with outside companies and the development and expansion of the niche market concept where the M-range and the S-range will reside, both claiming a biotope where true Leica DNA can be cultivated.

The main selling point for the Sumo-Leica is the amalgamation of medium format image quality with 35mm ease of handling and speed of operation, allowing a new style of photography related to documentary photography in all environments (the weather sealing of the S2 is a point in case). Indeed, the weather protection and the excellent close focus performance of the lenses are a direct attack on the Hasselblad and Phase One camera systems that are studio based, have limited open field deployment and provide lenses that are not so good wide open and at close ranges.
The S2 however has to convince two totally different populations that they have a non-refutable offer. The Nikon/Canon must be seduced by the improved image quality compared to the 35mm sensor sizes in the D3 and 1Ds models. This improvement needs to off-set the operational flexibility and depth of system of the Nikon/Canon systems. Canon/Nikon users now already complain about the unwieldy sizes of the image files, but are very happy with the scope and depth of the camera system. The Leica S2 system at the start is extremely shallow in its system components (a handful of lenses, no elaborate flash systems etc).
The S2 needs to convince Haselblad and PhaseOne users that a new style of taking pictures (in the field, hand held, eye level) is worth switching to the S2 domain, that could deliver the same image quality, but not a significantly better image. The question is whether the clientele for current medium format imagery will accept the documentary approach that the S2 supports.

The Sumo-Leica, however convincing the concept, will not sell simply based on the specs. Actual performance and comparison tests have yet to appear and what is being distributed in the public domain, are impressions by carefully selected S2 evangelists. These enthusiastic remarks need independent corroboration to establish a base of facts to rely on for comparison and assessment. The other issue is the promotion of that new style of medium format photography that the S2 invites to explore. Without a sustained and serious marketing effort by Leica, the concept will not take root and in this respect the Leica marketing department really needs a refreshment.

Leica, almost by tradition, is no technology leader, but capable of a high level of perfection. With the design and marketing of the S2 Leica proves that they are willing to take the plunge into unchartered terrain and redefine themselves as technology innovators by intelligently combining and enhancing third-party components (sensor by Kodak, processor by Fujitsu).

The Leica S2 is undoubtedly a camera for a niche market. This is the domain where Leica feels at home. The company lacks the aggressiveness and unlimited R&D resources of the high end Japanese dSLR competitors and lacks the tradition and the in-depth knowledge of the requirements of the broader medium format market. The niche might be too small to support the continued exploration and evolution of the S2 concept and possible spin-offs.

The significance of the Sumo-Leica lies not in the Pro format as such (bigger sensors are available in the medium format market), but in the attempt to promote the classical style of 35mm photography in that staid segment of photography. When the Leica R8 was introduced some commentators (Geoffrey Crawley and myself among others) noted that this SLR was in style and concept as close as possible to the CRF philosophy of the Leica M-range. Such a remark cannot be made about the Sumo-Leica. The weight and size of the S2 (why are specifications not yet available?) are not in the same class as the Leica M reporter camera, but the profile that Leica is drawing for the S2 (weatherproof, fast operations, very high quality) are related to the type of eye-level handheld spontaneous photography that is the hallmark of the M line.

The S2 does make a novel proposal in the medium format digital market (the 2:3 format is new as are some of the characteristics, specifically the propensity for outdoor shooting). But the Sumo-Leica has to confront a fight on two fronts: on the offensive side, the S2 must convince prospective users in the medium format market they the system offers decisive advantages compared to a well entrenched competition. On the defensive side, the S2 must hold off the phalanx of new DSLRs from Nikon and Canon who will claim to cover the same turf at a fraction of the cost and with minimal loss of image quality. A wise general would not like to be in the position to fight on two fronts at the same time.

The success of the S2 hinges on the ability of the Leica company to create a convincing and very finely honed profile for the camera and a clear roadmap for the future. The dynamics in the world of digital capture are such that a camera hardly has a useable life span of more than two years.
Photokina 2010 will provide the answer.

Leica S2: the new paradigm for post-modern photography?



The absolute clean body shell is the first thing you notice when you hold the S2. The second surprise when you look through the finder is the uncluttered, bright and large focusing screen. The structure of the screen surface is eminently suited for manual focus. You can focus precisely and quickly with this screen. You can place the focus plane on the subject where you want because the screen shows the sharpness from corner to corner. The right hand works on the shutter release, the shutter speed dial and the click wheel with which you select functions and options. The layout of the camera forces you into the classical position: left hand supports the lens and handles manual focusing, the right hand selects the speed and aperture and activates the release button. This button is hypersensitive and many accidental exposures are the result. Selecting the options (white balance, ISO setting, exposure metering method, exposure compensation and so on) must be done by scrolling the click wheel through a menu list and press the wheel to select the option and change the settings. This action asks for some time and cannot be done in a hurry. In fact this new S2 has been subject to an austerity policy that makes the classical Leica R9 a luxury package. When discussing the S2 design and strategy with Mr. Lee, who, to be fair, has been the driving force behind the Afrika project, he said that he wanted to position the S2 outside the mainstream of current camera design thinking to avoid a head-on competition he was certain he would loose. He also wanted to highlight the time-honored Leica virtues: solidity, durability, simplicity and performance. The camera shape must embody and stress these virtues. A deliberate and considered approach to the art of picture taking is required to exploit the image quality made possible by the large sensor and a new range of lenses. The thinking behind this camera places the photographer in the center of the photographic process. There are basically two approaches in photography. One is the approach of pre-visualization where the photographer thinks about the picture and can arrange the scene or afford to wait for the scene to materialize. Iconic examples are Henri Cartier-Bresson and Ansel Adams. The other one is the approach of the snapshot where the photographer hunts for scenes that vibrate with a state of mind or inner compassion. Iconic examples are Robert Frank and Ed van der Elsken. The photographers named here used 35mm cameras and medium format cameras.

The S2 has been designed for the pre-visualization approach. The creative process starts already before the picture is taken. The selection of ISO speed, exposure measuring method, exposure compensation, exposure mode is made based to match and support this process. You select these settings before the shooting and when the photographer is engaged in the creative process the camera is a full extension of his intentions.
To appreciate the new thinking of Leica on camera functionality, I will present a brief overview of the development of camera functions. With the original Leica camera, you had to guess distance and exposure and you had to set distance, aperture and shutter speed manually on a scale and with a dial or knob. Later a coupled rangefinder was incorporated into the camera body, a feature that in those days could be referred to as 'automatic'. The exposure had to be measured by an external meter, but the Leica M3 had an exposure meter that mechanically coupled with the shutter speed dial. The major breakthrough occurred with the Konica Autoreflex that incorporated a fully automatic exposure metering system. Such level of automation did upset the professional community. Autofocus was added to the list of automatic functions with the Minolta 7000. The progressive replacement of mechanical linkages by electrical and electronic components in combination with a increase in calculating power by the microchips made possible the addition of many more functions, culminating in the Canon T90. The last film-loading Nikon camera, the F6, offered a multitude of autofocus options, exposure metering systems, shooting modes, flash control and film advance modes. The fact that the focusing screen area could be segmented into a number of independent points that could double as sensitive areas for focus detection and luminance reading gave additional possibilities for precisely controlled metering of focused points, single or in combination. Powerful algorithms that could analyse all the data collected by the luminance and distance 'sensors' gave rise to sophisticated programs for automatic exposure determination, balanced fill-flash, dynamic and static focus tracking and more.
The incorporation of a solid state capture medium into the camera to replace the silver halide emulsions added even more functions to the camera. The image sensor could have more image sizes in amount of pixels, there is a choice of file formats, white balance options and ISO speed settings. The LCD monitor had its own and separate group of display options.
The list of options and combinations is almost endless, but an interesting trend became visible.
The powerful algorithms were so efficient that the camera could operate on auto pilot so to speak and find the optimum settings for focus, exposure, sensitivity, and color adjustment. The camera engineers however gave the user the possibility to override and compensate whatever settings the program did propose. And another range of options was created like manual focus point selection, focus bracketing, exposure bracketing, over/under exposure correction and flash control.
It is evidently impossible to manipulate all these functions while taking pictures. Therefore the user can combine some groups of functions and settings in custom profiles that can be selected in a simple manner. The large amount of controllable functions asks for control and input devices and modern cameras are littered with buttons and wheels and display screens that constitute the user interface.
Now let us lean back for a moment and reflect on where we are after twenty years of relentless expansion of camera functions. We have quite sophisticated programs that can fully automate all camera functions to a high degree of precision taking into account all kinds of environmental parameters. But we cannot trust this automation in many situations and need bracketing and override functions to adjust the proposals made by the programs. We should also reflect on the fact that the best exposure follows the incident light method and that adjustments to reflect the intentions of the photographer are within one and a half stops. When using studio flash the photographer needs to measure main and additional lights to balance the amount of light. And when using flash in combination with ambient light the photographer also needs an intelligent judgement.
The upshot is this: sophisticated automation delivers excellent results, but never better than when the photographer knows what he is aiming for. And the other side of the coin is of course that all the automation in combination with the overrides and adjustments distracts from the basic photographic process. Reviewing all the functions we can separate them in four distinct groups:
(1) the core photographic functions, like focus, exposure, flash control and transport.
(2) the functions that emulate film properties like ISO speed and color temperature
(3) the sensor related functions like file format, storage and image size
(4) the monitor related functions like live view, display and viewing options.

The Leica designers of the S2 reasoned that the S2-photographer would be most interested in the image quality of the picture. To create maximum performance the photographer should be able to anticipate and envision the circumstances where the pictures are going to be made. It is in fact a rare situation where light levels change so rapidly that an instant alteration of the ISO speed is required. In general we may question the need to have instant access to the many functions that override or change the initial settings. The priority for a photographer lies with an efficient and fast use of the group of core functions.

The Leica S2 camera body is very clean and closed. The claim that the body can handle adverse environmental influences is undoubtedly related to the fact that the body itself has hardly any openings at all. No need for elaborate sealing!
The main functions from the first (core) group can be selected with the combined shutter speed dial and click wheel with one hand. Once you know the sequence it is very easy to do and very convenient too. Basic functions from the other groups can be found through the menu options and the menu control buttons with color coded function groups.
The creative and technical adjustments of exposure and focus are directly accessible and here we find the core of the Leica S2 approach. The camera generally offers the manual adjustments first. But you can set all important control functions on Automatic and let the camera do the job.
The click wheel lets you select the operating mode (manual, A, P, T) and depending on this choice turning the wheel selects the aperture. This control is a major change in Leica way of thinking as the company has always claimed that the lens should have a true aperture selection ring.
The S2 concept however shows a quiet recalibration of Leica's new approach to photography.
Looking through the finder you see the cross hair where focus and exposure is determined. The screen is a joy to work with. It is large, bright, very fine grained, but sensitive enough for precise manual focus. The AF performance gives mixed feelings. The focus movement is quite fast, even in dim light, but not very accurate. In many situations the AF is nervous, not finding a definite lock. The best option is to use the manual focus with AF confirmation. Really nice is the finder indication with arrows that show the focus movement direction for AF confirmation. This works fast and it is secure. It also gives the photographer full control where to place the sharpness plane in the scene. Leica is understandably modest in its claims about the autofocus capabilities. The S2 is evidently designed for the photographer who is in control of the scene, knows the goal and aims for the ultimate image.

The camera is heavy, but most users of big Canon and Nikon cameras judged the size and weight favorably. When the 180mm with attached lens hood is added to the camera body, the combination is impressive, and one would have trouble to extract the best quality when handholding the combo.
For the maximum performance a slower working pace, a tripod and manual focus are the three basic requirements. In this photographic environment, AF is not an essential ingredient. The AF mechanism has its own detection procedure which does not always synchronizes with the ideas of the photographer. AF is often nice to have, but in demanding situations manual focus with AF confirmation is best. The lenses are designed to support the manual focus option: the focus movement is smooth and firm giving a heightened sense of confidence in the focus accuracy.
The shutter release is very sensitive and works almost without any delay. The operating noise of the shutter and mirror is low and the sound is quite pleasant, one would even say melodious to complement the solid and functional feeling of the camera. There is however one curious point to observe. Holding the camera firmly to the eye, one can definitely feel the impact of the mirror damping action. Additional research is needed to see if this action will introduce vibration of the body during the picture making stage. You can always select the mirror-up option when in doubt.
The DNG image files are 76 Mb in size and while the processor does a good job in processing this amount of bytes, the speed of processing in combination with the buffer size is slow, especially if you want to take two or three pictures in quick succession. Here again we note that the camera is not for fire-at-will shooting, but for deliberate image creation.
The exposure in all modes delivers slightly over-exposed pictures, the designers here follow the not yet proven advice that in digital photography you should modestly over-expose to get the best from the highlight section of the dynamic range, while minimizing the use of the deep black section to avoid noise. Sensitivity of the meter equals the sensitivity of a classical CdS or selenium exposure meter with a range from EV1.7 to EV20.
To summarize this part of the S2 report:
The S2 reflects Leica’s attempt to recalibrate the digital photographic workmanship: the combination of maximum image quality, a manageable body shape and size and a user interface of stark simplicity places the photographer once again in the commanding role as it was when the first Leica camera was released to the public. The esthetics of the body shape may not generate universal acclaim, but once you have the camera in your hand and before your eye, the appeal of its design and operating simplicity is difficult to resist and certainly touches the nerve of a the pure photographer.
The alpha and omega of the concept however resides the attainable image quality. This will be the subject of the next parts.

Leica S2: the lenses: a technical analysis


A very famous comparison by Geoffrey Crawley of BJP fame confronted a modest and cheap medium format twin lens reflex of Chinese origin with a high grade 35mm SLR of Japanese origin. His conclusion was that the larger size of the negative fully compensated the much higher lens performance of the 35mm camera. All medium format and large format camera makers relied on this rule: the larger the negative the lower the lens quality can be. The logic is evident: a large negative requires less magnification and lens aberrations are therefore less magnified too. If a 35mm negative requires good quality at the 40 lp/mm level, a large format negative needs at most good quality at 10 lp/mm for a bigger sized print.
This rule holds even today in most medium format digital backs and cameras.
Leica is the only company at this moment to couple high quality lenses to medium format sensor sizes. I could examine two lenses: Summarit-S 1:2.5/70mm ASPH and Apo-Elmar-S 1:3.5/180mm.
These lenses represent the current benchmark in medium format lenses. This is not a feel-good statement, but a claim that can be proven with hard facts. For high fidelity photography the reference point is the contrast at 20 lp/mm. Below you can find a number of classical designs with the contrast value for the on-axis position at full aperture. The numbers are generated with the well-known Zeiss K8 equipment.
  • Planar 2.8/80 55%
  • Summarit 2.5/70 82%
  • Makro-Planar 4/120 72%
  • Sonnar 4/180 78%
  • Superachromat 5.6/250 80%
  • Apo-Elmar-S 3.5/180 90%

The famous Zeiss Superachromat has set the standard for performance in the medium format domain for a very long time and compared to other lenses it indeed is an outstanding performer that has had no challengers. The new Apo-Elmar-S outdoes and the Summarit 70 equals the Superachromat. Note that the Leica Summarit reaches the same value as the Superachromat wide open that is more than two stops wider. Now it is true that one merit figure cannot represent the full quality of a lens, but it is an indication when you compare the numbers generated by the same equipment under identical lab conditions.
The focus difference is for the Superachromat a stunning 0 (zero!) micron at f/11.
The Summarit has a focus difference of 22 micron over the aperture range from 5.6 to 22. The Apo-Elmar-S has a difference of 27 micron at f/5.6. These values are really excellent and at least twice as good as what you see from other comparable lenses.

The MTF graphs on the Leica website may give a comprehensive overview of the quality of the S lenses in general. Below you find a range of graphs that show the MTF numbers as measured on the K8 equipment. The correspondence between the two sets is very high. The Summarit has an interesting shape for the 40 lp/mm. It has the familiar Leica fingerprint of a drop in contrast at the image height of 15mm. That the curve rises upward after 18mm is caused by the slight amount of vignetting at the corners. It is well-known that vignetting will improve the performance in the edges as the most vicious rays are cut off from the image forming process. The drop in contrast is hardly visible in general photographic work, but can just be visible at big enlargements when you know where to look. The shape as it is, is not accidental but intentional because it will balance aberrations such that the critical 5lp/mm and 10 lp/mm deliver high contrast values.
The curves for the Apo-Elmar-S are exemplary and one would be hard pressed to find a better lens. The design is derived from the highly acclaimed Apo-Elmarit-R 2.8/180mm, a lens that is one of the benchmark lenses for the R system.


One of the claims of Leica for the S-system lenses is its good close-up behavior at wider apertures. Tests did show that this claim is fully substantiated. (real-life examples will be shown in the next part). While not of truly macro-quality, the Summarit can be used with full confidence at closest distance wide open and you can expect best image quality with excellent definition and contrast.
When discussing lens performance of 35mm systems, it makes often sense to study the zonal behavior, that is the difference in image quality when you go from center to edge. For the S-lenses this is a redundant exercise. The lenses I used were sharp from corner to corner and even wide open you cannot fault the quality. It is most frustrating to sit behind the K8 equipment and note that the measured numbers being displayed on the monitor are so consistently high at all apertures and image points. You cannot help thinking that such performance cannot exist and that there must be weak points. But I am afraid that frustration should be exchanged for admiration.

The amazing lens performance has one drawback: the size and weight of the lenses makes handholding them a tough job. The classical rule that you can safely handhold a lens at a speed equal to the reciprocal of the focal length does not work here (and I might add it never was a valid rule). The S2 and its lenses require at least 1/1000 for good results.

Without the lens shades the lenses are a bit sensitive to flare and it is indeed possible when shooting with the rays of the sun obliquely entering the front glass surface to create light patches.

The analysis above is restricted to the optical/physical characteristics of the lenses. The S2 has a digital sensor and the lens behavior should be related to the sensor characteristics.

The OECF measurements at ISO160 show a dynamic range of eight to nine stops and a moderate noise, but the noise is well controlled as can be seen from the behavior of the RGB channels. Leica has given much attention to the clean differentiation of shadow detail and tonal values and has controlled noise effects. The behavior at ISO1250 is significantly lower, but one should realize that the S2 is not a camera that will be used at these ISO speeds quite often. At a reasonable mid position of ISO640 image quality is very good. And let us be real: ISO400 has served most photographers for decades with good results. I am not inclined to follow the demands of many commentators that one should strive for extreme values to feel happy. A bit of moderation is not a bad thing in these our modern times.
In AgX days there was an easy and simple method to measure dynamic range. It was based on the zone system. You photograph a grey card and over/underexpose for seven stops and you can then easily measure the density values of the negatives. The same is possible with digital capture systems. This I did with the S2 at ISO160 and ISO1250.

It is known that the highest value where you can see differences is 245 and the lowest value is 4. Using these reference numbers I got a range of +4 to -4 for ISO160 (eight stops) and -4.5 to +4 for ISO1250 (8.5 stops). The noise reduction algorithm of Lightroom 3 Beta could reduce the color artefacts but not without softening the details. The high ISO values of the S2 are interesting as emergency options. The S2 will be deployed under conditions where the best quality is required and then you may assume there will be amble illumination.
For numerologists the following measurements may be of interest: the maximum Nyquist resolution is 2500 lp/image height or 82 lp/mm in classical words. The Summarit-S at f/2.5 resolves 2000 lp/ih or 66 lp/mm which is an outstanding result. The lens optimum is at f/5.6 where the resolution is close to 2400 lp/ih, close to the Nyquist maximum. The Apo-Elmar-S has slightly lower values, but the higher magnification will compensate this to a large degree.

From the technical analysis of the S-lenses the conclusion is evident: the lenses are at the top of the medium format league and a quantum leap in quality compared to the competition and also to the M-series of lenses. The quality that you can get with the S-lenses will never be available in M-lenses. The lens quality is quite tightly related to the possible size of the lens. And M-lenses have to be small! It is on the other amazing how good the M-lenses are in comparison to the S-designs.


Leica S2: the lenses: a litmus test


In the previous part I concluded from the technical analysis that Leica has been able to position the new S-system at the top of the medium format league. Some readers remarked that it was unfair to compare new lenses with older Zeiss lenses for the H-system. That is a point well taken. The current lenses for the PhaseOne, Mamiya, Pentax and Hasselblad digital systems generally do follow the design parameters of the classical Zeiss lenses. In this perspective it makes sense to compare the design philosophy of Leica with those of the competitors. A second point is the influence of the sensor size. You might argue that the introduction of 50Mp and 60 Mp sensor sizes will redraw the medium format landscape again. But the law of diminishing returns does work. The jump from 18 Mp (Leica M9) to 24 Mp (Nikon D3x and Sony 900) to the 37.5 Mp of the S2 is visible but the improvements in quality are slowly becoming academic and the need for image files based on 60 Mp capture systems is limited, if you are able to see the differences. More on this theme in the next part.

In this article I will present a number of actual pictures to deliver proof of the capabilities of the S2 system and lenses. The method I used is the same for all pictures presented here. Leica has stressed the fact that the S2 images do not need a large dose of postprocessing as the basic RAW files are already excellent. The logic is compelling: a professional photographer should be fully confident in the capabilities of the system and spend most time in taking pictures and not in manipulating image files.
All pictures presented here are sections of the RAW DNG files developed with the new final version of Lightroom 3. The pictures are not manipulated in any way, no exposure or color corrections and no sharpness manipulations. It is always possible to improve on any one of these pictures, but for comparison purposes all processing is identical. The only exception are the black&white portraits that were based on the raw DNG files with Lightroom presets. All DNG sections were converted to JPG by the Lightroom engine.
Many users of the M8/9 system have observed that the impression of the images is flat and lack the visual depth of chemical prints and slides. This difference is indeed one of the reasons why film is still in demand. The plasticity of round objects in a scene, the subtle tonality in the highlights are characteristics of film not easily found in digital files.
The S2 images did strike me as being as close to film-based pictures as I have ever noticed. The S2 system is quite close to implementing the Kodak E-6 strategy: take the picture, develop in E6 and present the slide.

The general quality.



The Summarit-S 70 and Apo-Elmar-S hardly improve when stopping down and have a very even coverage over the full image area. The images are selections from the center star and the upper left corner star. The performance of the Summarit wide open is excellent with only a slight drop in contrast and definition at the edge.
At f/5.6 the center and edge performance shows a higher level of crispness, but the edges are still faintly lower.
The same pattern is seen in the Apo-Elmar-S performance. The slight loss of contrast at the edges is also seen in the MTF graphs. I should stress that these differences, while visible in the test pictures, loose much of their importance in actual picture taking.
The quality of the image as far as definition is concerned stays on a very high level when higher ISO values are used. See the picture below of the center part at ISO1250 with the Summarit-S at f/5.6. The noise pattern is on the other hand clearly visible: see below the comparison of a patch at ISO160 and ISO1250.
Pictures at various ISO values indicate that for critical work ISO640 is the maximum. But even that speed is very high for a medium format camera.



Leica S2: a comparison



Background


In the heyday of AgX photography camera manufacturers tried to design and develop products that offered distinctive features compared to the competition. The differences between cameras were meaningful as they were tailor made for a specific group of practitioners. The question what is the best camera did not make much sense. A Nikon F was more reliable than a Pentax Spotmatic and a Hasselblad more durable than a Pentacon Six. The choice between a Hasselblad or a Rolleiflex depended on the needs of the photographer and his style of picture taking. Geoffrey Crawley of (old)-BJP fame refused to make comparisons between cameras as it was often comparing chalk and cheese. He preferred to do a lengthy analysis and provide the reader with a detailed profile of what a camera can do and what the user can expect from the camera. This approach is no longer practicable. Cameras are now often clones from each other and the commercial life of a camera is shorter than the period it takes to do a thorough investigation.
The current pre-occupation, one might even say obsession, with finding the best product is a delusion, but strongly promoted by magazines and internet forums. I am not aware of any workable definition of 'best'. What we have is a ranking based on a small and often not representative range of measurements. The assumption is that a camera with a speed of 10 frames/sec is twice as good as a camera that only reaches 5 f/s and a camera that resolves 2739 lp/ph must be better than one that resolves 'only' 2496 lp/ph. The camera that gets 74 points is a loser compared to a camera that gets 74.5 points. At least this is what the magazines and websites want you to believe and accept.
Basically there is no best camera or a top five best ranking cameras. The truth of the matter is that there is a best selling list, but the best selling books are not the best of literature. There is also a 'best for you' camera, but that one does not need to be in any top ranking list.

Comparisons between camera features and performance are informative if it helps an interested photographer to make a well-informed and balanced decision. Comparisons should be informative in order to clarify choices and needs. Much noise has been made about the IR-sensitivity of the M8 or the high level of noise at high ISO values of the M9. Both facts are true in the sense that these characteristics can be demonstrated and with the right equipment can even be measured. But if you only work in black and white the IR sensitivity might be a benefit and when you never use high ISO values the noise is not an issue. If you value the rangefinder concept and exquisitely built products the M8 or M9 might be best for you and then the ranking on some list is irrelevant.

I made comparison pictures with the S2 and 70mm and 180mm lenses next to the Sony A900 with Zeiss 1.8/135mm, with Nikon D3X with new 1.4/50mm and with M9 with 1.4/50mm. The apertures used were f/4 for the telelenses and f/2.8 for the standard lenses. All images are made with manual focusing to get optimal quality and not introduce AF differences.
The scale of the pictures is always 1:1 and the size therefore different.
The pixel dimensions are
M9: 5212 x 3468; Nikon and Sony: 6048 x 4032; S2: 7512 x 4992.



Definition



The highest definition and the cleanest image is being provided by the S2, followed by D3X and A900 and the M9.
What we see here is the classical rule that negative size matters. The annex to this rule is that size differences follow the law of diminishing returns.
The jump from 24 Mp to 40 Mp is numerically high (a +50% increase), but qualitatively the image quality does not increase by that same percentage. What matters however is the fact that the S2 delivers the goods without any postprocessing and so reduces the time the photographer or his assistant needs to operate the computer which is a valuable gain in productive time. And if you are following the AgX approach that taking pictures should cover 70% of the time spent on photographic activities, the S2 will support this attitude.

If you look critically at the pictures made with the M9 and D3X (disregarding for this moment the color differences) you will note that the Nikon images are crisper and tighter, but again the differences are not substantial and depending on what you want with your photography all four cameras can deliver.
All of these cameras support a different mode of photography and the performance should be seen in the appropriate frame of reference. One aspect is emerging as of overriding concern: the interdependence between software, lens quality and camera performance. In the case of the M9 and the S2 the quality of the lens is beyond reproach and in this case the software and the sensor do not influence the result. This is the current Leica design approach: sensor quality and lens quality are the defining parameters (as in the past lens and film emulsion). In the case of the A900 and D3x the interaction is less clear, but the influence of the sensor coupled to a lowpass filter and the intelligent in-camera processing can enhance the basic performance.

In the next part I will return to a more in-depth comparison between M9 and S2.

Leica S2: the Leica way of photography


Reviewing a camera system as important as the Leica S2 has to follow two different and complementary approaches. The first approach is the purely technical analysis where you try to find the performance limits of the camera. These limits delineate the expectations of the user and the best possibilities for its deployment and use. It is one the most common fallacies in the digital photographic community that the primary role of a test is to provide data for comparison with other products and for purposes of ranking. Comparisons and rankings have only a limited value. The fact that they are so prominent in modern photographic discourse is basically a sign of misguided number fetishism and superficial thinking. In most cases it does not provide the reader with meaningful information from which to derive intelligent decisions about the product under review. It is informative to know that lens A has a MTF value of 50/50 (% contrast/linepairs.per.mm) on axis and 20/20 in the corner and that there is a 2 stop vignetting wide open. The corresponding values for lens B might be 40/50 and 30/20 and 2.3 stops. These results might help you decide what lens is best for your style of photography.

Technical analysis and the problematic rankings


This is the real use of numbers and performance limits. It is always possible that you can create with some number juggling a merit value of 3.1 for lens A and 3.2 for lens B or the other way around. Is this ranking useful for the decision making. You may seriously doubt it! The basic problem lies in the fact that many measurements have only a very shaky relation to photographically important components of image quality. This relation is even more problematic in the digital world where we see two diverging trends. On the one hand we have very potent post processing software to tame the restless pixels we are looking at. The very powerful manipulations of the software do change and diminish the value of performance differences that are present at the start of the imaging chain. And on the other hand we have our screens where we can enlarge individual pixels to unrealistic sizes to see all kinds of aberrations that have no practical value. It might be a sobering thought that in AgX days the study of the grain under the microscope was considered as a useless exercise for scientists-turned-photographers because of the extreme magnifications. Under the microscope you can look at grain sizes with 100 times enlargement when in practice you hardly use 15 times. The same is true for pixel peeping: you look at pixel sizes that would require a print size of several meters wide, when you at best will print A3. One might argue that the computer screen is the preferred viewing medium for digitally constructed images. There is some truth in this, but one should also realize that a picture should be looked at with the size and from the perspective that the maker intended. In AgX days no one would have looked at grain clumps as a substitute for the image or as a relevant measurement for performance.

Expectations and performance limits


The second approach will register the behavior and the performance of the camera in practical use. This is a subject bristling with pitfalls. It is a necessary complement to the technical analysis. Technical performance tests cannot cover all conditions that will occur in practical shooting situations. Even today, after nine months of daily experience with the M9 I do detect new and additional facts. One must realize however that practical picture taking can range from a sublime lucky shot over unimpressive middle-of-the-road images to plain mediocre pictures. There is a grave responsibility in this area for a reviewer. If you only present the best shots you will increase the expectations for the camera/lens system and users might be disappointed when they do not equal the achievement in normal use. The other approach is to use the average results, but then you will definitely harm the standing and prestige of the camera. It is here that the comparison with the technical performance tests is really advantageous. The technical tests show you what is the maximal attainable quality. The practical tests can show you where you stand with your expertise. Any prospective user of a camera/lens system should be aware that the maximum is not the usual. And you need to define for yourself what the performance level is that makes you or your customers happy.

Owning a car with a maximum speed of 200 km/h, does not imply that you have to race at that speed whenever possible. You find a speed where you feel comfortable and fits the traffic conditions. Most public examples of S2 images are shot by fashion photographers who customary use tripod, flash, small apertures and medium distances. The strong points of the S2: easy handling for handheld shooting, weatherproof design, excellent optical quality at wide apertures and close distances are not covered by this fashion-style imagery. This approach might be necessary for Leica to obtain a firm footing in the professional market, but it neglects the basic claim of Leica for the S2 as a revolutionary new format camera reminiscent of the introduction of the original Leica I that made the 35mm format fashionable. The fashion photographer’s overriding concern is to get the best shots for the customer and to have a reliable system that delivers the required pictures with great certainty. A second chance is often not possible and bad results will certainly destroy the reputation. The Leica S2 is an easy to use reliable camera that delivers very predicable results.
These are important aspects for a fashion or product photographer and in general a bonus for any user.
The important point is to have a camera system that brings the results you want in a stress-free and fuss-free manner. It is absolutely irrelevant where the camera stands in the picking order of the photographic magazines or websites.

S2 and M9: different but with Leica DNA


The results of the technical tests show that the M9 is very close to the D3x and the S2 is ahead of the D3x. As I noted above, performance comparisons should always take into consideration the bandwidth of performance and the additional tolerance range that is inherent in every measurement and comparison. Test results need to be qualified with the famous 5 to 10% of tolerance that is caused by production tolerances in combination with the variations in lab equipment and human errors. It is really a pity that no serious magazine or website - I know of - does acknowledge this inevitable variation in results and cautions the reader to interprete the presented results with this bandwidth in mind. Much needless bickering and railing against others could be evaded if we accept that results are not accurate to two or more decimal places.

Against this background I used the S2 and M9 in a more informal manner to find differences in use and similarities that underscore the famous Leica way of taking pictures.
The two Leica systems represent two totally different design philosophies. The M9 starts with the minimum size of the camera and therefore the physical limits of the optical system are a given constraint. The maximum performance of the M9 lenses is determined by the size. If size is no problem you can design a super lens (see the gigantic lithography lens systems), but if you have physical restrictions a compromise is necessary. The art and science of Leica M lens design is the balance of size with maximum image quality. The forte of the M-system is the compactness of camera and lenses in combination with the exquisite performance that is so good that it can challenge much bigger systems.

The S2 design started from a different premisse: establish the desired performance and let the size expand to fit the requirements. The S2 lenses are rather big and the camera size has to match. The performance in lab conditions is without doubt a quantum leap ahead of the M lenses al be it at lower maximum apertures. If you switch from M9 to S2 or the other way around, the low weight and compact size of the M is immediately evident. The basic feeling that the M is a discreet and effective extension of the eye of the photographer settles in your mind. You are part of the scene and its developments. The S2 in contrast is a big camera, not as big or intimidating as the D3x, but still a fistful of finely shaped metal. Looking through the finder will evoke reminiscences of the Leicaflex and find similarities with the M rangefinder. The S2 has a central AF patch which has the same functional limits as the M rangefinder. You intuitively focus on the main subject of interest and neglect the overall composition. But you can use the total screen area for focus confirmation and that is how the later Leicaflex screen worked. The S2 screen is very bright, clean and large and literally invites you to compose your picture. But you lack the intimate rapport to the scene and subject. The classical functional distinction between a medium format reflex camera and a small format rangefinder camera did not disappear when both systems went digital and more automatic. The S2 relates to the M9 as Richard Avedon to Robert Frank. The S2 design and handling have nothing in common with most medium format cameras, film-loading or solid state. The S2 is the first medium format camera with the ease of handling of a compact rangefinder. Switching between both systems is seamless and you hardly need an adjustment process. A small regrouping of the hands and fingers and you are already familiar with the operational functionality of the camera. The S2 delivers the impeccable technical qualities of the Avedon-style of photography and this quality is even available when you use the lens at maximum aperture for razor thin depth of field and sharply defined focus. The uniqueness of the S2 is not the performance margin (as I said in my report there are other cameras that deliver comparable quality), but the marriage of the rangefinder approach (close distance, wide aperture, selective focus, fast operation) with medium format image quality and a new paradigm for lens design in this format. An additional bonus for many photographers is the excellent image quality out-of-the-box. If you wish there is no need for elaborate postprocessing and this is part of the timeless Leica approach: the quality should be fixed at the negative stage.

All the pictures discussed are original DNG files without any manipulation, except the black&white conversion with Nik Efex in Lightroom 3 and illustrate the leitmotiv of this article: performance in itself is not the most important argument for the choice of a camera system. The performance should match the required image quality that the photographer needs and should fit his/her expectations.


They are an indication of the performance potential of the S2 and M9. This juxtaposition might seem to be unfair for the S2 image. The portrait taken with the M9 was taken with the 75mm lens and the portrait taken with the S2 used the 70mm at the same distance. The detail definition and crispness of the S2 image is higher than in the M9 picture. The quality potential of the S2 is evidently very high and this is important for the type of assignment that the S2 will have to handle. The comparison also underscores the claim made by Leica that the S2 lenses represent a new level of performance in the medium format world. The image below is a section of a portrait that honors the differences in sensor size.

There are two sides to every question and one should ask whether the performance of the M9 matches the quality aspirations one does cherish. The picture below shows a section of the DNG file taken with the M9 and the SX-M 50mm ASPH. This performance satisfies me and I can always move closer and/or use a 75mm or 90mm lens if I need more.

Upshot



The whole idea of a simple merit figure with a clearcut performance profile is a proposition too naïve to be acceptable. The photographic content and the photographic image quality are connected by a very complex relationship. Knowledge of the technical possibilities and limits of a camera system can contribute to a better understanding of this relationship, but in the end the photographer makes the decision based on what he/she wants to achieve.
As a closing remark I may recall that the two designers that made modern photography possible, the Barnack/Berek combination, never looked at the rule of the maximum, but always had a different ideal in mind. They asked themselves the sensible question what is needed to allow photographers to explore a new visual world and created a compact full metal camera that could be firmly and conveniently held before the eye with a lens that had enough depth of field to allow for zone focusing and made possible the art of the snapshot. Berek himself noted in the Leica Brevier that he specifically had not opted for the maximum as this would have restricted the use of the camera. It would have been easy to design an f/2 lens for the Leica I (an f/2 design was no rocket science even in those days), but the thick emulsion layers of the film would have produced unpleasant defocus effects. The M9 and the S2 are the two professional systems in the Leica catalogue. The M9 is in its ninth edition and has a long heritage where the S2 is in edition one and has a bright future. We do not know what the S in its ninth edition will be, but we can be sure of one thing: the speed of technological innovation is much higher than in the previous decades when the M evolved from Number Three to Number Nine.