Leica R-Lenses manual Aperture Stop

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of fine detail. Stopping down to 5.6 the performance of the centre now extends over an image circle of 12 mm diameter (see image 3). There is no trace of astigmatism and a slight field curvature. Some colour fringing is visible at very high magnifications. Distortion is visible with -3% (barrel distortion) and so is vignetting at 2.5 stops (see image 4).

At 35 mm and full aperture (2.8) there is a small improve- ment in the outer zones where the lens now records 100 lp/mm with good micro-contrast (see image 5). Distortion now is about -1%. At 5.6 we have optimum performance with a crisp rendition of very fine detail over most of the image area (see image 6). Vignetting is practically gone (see image 7).

At 50 mm and full aperture (3.4) we see a very high con- trast and an exceptionally high resolving power of more than 150 lp/mm over a large section of the negative. There is still some faint colour fringing, but in practice one would be very hard pressed to note it (see image 8 and 10). At

5.6we have impeccable performance that easily surpasses the quality of the Summicron 50 mm lens, especially in the outer zones of the field (see image 9).

At 70 mm and full aperture (4) the image quality becomes superb and we have an extremely high contrast and a very crisp definition of the finest details (see image 11).

Stopping down to 5.6 does improve edge contrast and now the corners are quite good too (see image 12). Distortion is 1% (pincushion) and vignetting negligible (see image 13).

At 90 mm and full aperture (4.5) the best performance is reached and compared to the 70 mm position the outer zones and corners are now as good as the centre of the image (see image 14). Vignetting is gone and distortion is very low with 1%. The low distortion at the tele side of the zoomrange is quite remarkable. Often the behaviour of zoomlenses can be characterized as good in the middle range and weaker at both extremes (see image 15 and

16).

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Contents Leica R-Lenses Chapter Leica R-Lenses IntroductionLeica VARIO-ELMARIT-R 28-90 MM F/2.8-4.5 Asph ZoomrangeOptical demands and mechanical con- struction Optical considerations ImageAperture Stop Aperture Stop Chapter Leica R-Lenses Image Oliver Richter Flare properties Conclusion

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.
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