Chapter Leica R-Lenses, Introduction

Chapter 7

Leica R-Lenses	1

__Introduction

The zoomlens as a species of lens design has had a strange evolution. The first design seems to be the Vario-Glaukar 1:2.8/25-80 mm for 16 mm cine cameras, created by Siemens around 1936. Especially in movies, the idea of a smoothly changing rate of magnification is very valuable as it can dispense of the stationary camera, moving on a trol- ley over rails. The first patent for a zoomlens is from 1902 by a USA company. The idea of a zoomlens is now more than a hundred years old. The first zoomlenses for 35 mm cameras were regarded as toys and even during the eigh- ties of the previous century the Leica company declared that zoomlenses would never surpass the image quality of fixed focal lengths. It is Mr Kölsch who deserves the credit for two major breakthroughs in Leica lens design: the aspherical surface and the high quality zoomlens. The semi- nal LEICA VARIO-ELMARIT-R 35-70 MM F/2.8 ASPH and the Vario-Apo-Elmarit-R 70-180 mm F/2.8 are the proof in the pudding: zoomlenses can be as good as fixed focal lengths.

Nowadays the situation is reversed: it are the fixed focal lengths that must prove their superiority against the chal- lenge of the zoomlens. There is no doubt: the zoomlens does not lend itself to high apertures (in the world of the digital camera this statement is not true!) and the maxi- mum aperture is F/2.8. But with current film technology the best ISO 200 and ISO 400 slide films (and 400 ISO BW films) can compensate for the one or two stops difference between fixed focal lengths and zoomlenses.

The zoomlens has a higher number of lens elements that can all be used to correct the optical aberrations and the designer has more tools to optimize his design. We know that with fixed focal lengths there is one optimum distance (or magnification) for which the lens can be corrected. In zoomlens design the same principle holds: there is only one focal length for which the design can be optimized. The choice is obvious: one can select the medium position, the wide angle side or the tele side. For the new LEICA VARIO- ELMARIT-R 28-90 MM F/2.8-4.5 ASPH, Leica has opted for an optimization of the 50 to 90 mm range.

The designer of a zoomlens has more tools to correct the lens, but the mechanical design and engineering are more demanding. There is clearly a difference between assem- bling a lens with 6 elements in a stationary mount and a lens with 11 elements in a moving mount. It is already a hefty task to manufacture and assemble components with a precision within 0.01 mm consistently. The additional requi- rement for a zoomlens is that this same level of accuracy must be maintained with moving components. Leica does check the precision of the lens with a testcycle of 50.000

movements of the lens mount.

This new Leica zoomlens has a number of innovative featu- res that elevates zoomlens design to a new level.

It is the first Leica zoomlens that has a zoom range above a ratio of 1:3, to be exact it is 1:3.214, very close to the magic mathematical number pi (3.14…).

The second innovation is a new and very elaborate mecha- nical design for the movement of the lens groups.

The third innovation is the ergonomics: the LEICA VARIO- ELMARIT-R 28-90 MM F/2.8-4.5 ASPH has one of the smoothest lensmounts I have touched, considering the fact that the lens has been made for manual focusing with a fully mechanical mechanism. The size of the lens is relative- ly small and fits in between the smaller Vario-Elmar-R 28-70

mmf/3.5-4.5 and the larger Vario-Elmarit-R 35-70 mm f/2.8 ASPH. That is quite good, given the additional focal length of 20 mm. The diameter of the lensmount could be held down by employing quite thin but very stable alumi- nium tubes. If you press very hard on the distance ring, you will increase the friction and this phenomenon has caused some users to question the mechanical stability of the new generation of zoomlenses. This is not the case, and one needs to get used to the idea that modern lenses have a different feel compared to previous generations.

The fourth area where innovations can be detected is the cosmetics: the lens has a beautiful shape and very impres- sive black finish.

We may add that the lens has its share of electronics with the electronic exposure compensation, useable with R8/9. No news here, but one should see it as a fifth area.

The ROM (electronic data and signal relay) contact ledge transfers information from the lens (focal length, aperture compensation and vignetting data) to the camera for cor- rect exposure determination and flash settings (zoom reflector).

R-Lenses specifications

Leica R-Lenses have long been revered by photographers for their exceptional quality and performance. Designed for use with Leica R-series film and digital cameras, these lenses embody the brand's commitment to optical excellence, precision engineering, and user-friendly functionality.

One of the most notable features of Leica R-Lenses is their superb optical design. Each lens is crafted using high-quality glass, often featuring special elements such as aspherical glass and low-dispersion lenses to minimize aberrations and enhance sharpness. This meticulous attention to optical performance ensures that images captured with R-Lenses exhibit remarkable contrast, clarity, and color fidelity, allowing photographers to achieve stunning results.

Another key characteristic of Leica R-Lenses is their robust build quality. These lenses are constructed with durable metal housings, ensuring they can withstand the rigors of professional use. The precision of the manufacturing process results in smooth focus and aperture adjustments, providing photographers with a tactile and reliable shooting experience. The use of weather-sealing in certain models allows for shooting in challenging conditions, further enhancing their versatility.

Leica R-Lenses also feature a distinctive aesthetic, characterized by their sleek design and distinctive red dot logo. This iconic branding signifies a level of craftsmanship and quality that is synonymous with the Leica name. The manual focus mechanism on R-Lenses is particularly praised by many photographers, as it allows for fine-tuned control over the focal point, which is especially useful in portrait and macro photography.

In addition to their optical and mechanical excellence, many Leica R-Lenses come equipped with advanced technologies. For instance, some models include the ROM (Read-Out Memory) contacts, which enable the camera to communicate with the lens for enhanced functionality, including automatic aperture control and accurate exposure readings. This integration of technology with traditional craftsmanship exemplifies Leica’s approach to modern photography.

Ultimately, Leica R-Lenses offer an unparalleled combination of optical brilliance, robust construction, and user-friendly features. With a range of focal lengths and specializations, from wide-angle to telephoto, photographers can find the perfect lens to suit their creative vision. Whether one is capturing landscapes, portraits, or close-up details, Leica R-Lenses provide the quality and precision expected from one of the world’s leading camera manufacturers.