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Telephoto lenses using diffractive elements to minimize chromatic aberration are commercially available from Canon and Nikon for interchangeable-lens cameras; these include 800mm f/6.3, 500mm f/5.6, and 300mm f/4 models by Nikon (branded as "phase fresnel" or PF), and 800mm f/11, 600mm f/11, and 400mm f/4 models by Canon (branded as ...
The EF 35mm f / 1.4L II USM is a successor of the EF 35mm f / 1.4L USM. It was announced at the 27th of August 2015 and is available since October same year. [1] The EF 35mm f / 1.4L II USM lens is the first lens in Canon line up to use a Blue Spectrum Refractive Optics element (BR element) to reduce the chromatic aberration at the blue end of the spectrum. [2]
As an L-series lens, it features two ultra-low dispersion (UD) elements, and utilizes Canon's ring USM for fast and silent focusing. It has a push-pull zoom design with the possibility to lock the lens at the desired focal length. The lens exhibits strong barrel distortion and chromatic aberration at the wide end.
The two 5.6 versions were contemporaries, launched at the beginning of the Canon EOS system. The L version had a different optical construction which improved sharpness, color, and chromatic aberrations. Otherwise the lenses were physically similar. Canon decided to upgrade the non-L version in the early 1990s to the 4.5-5.6 version, not the L.
The Canon EF-S 18–55mm lens f / 3.5–5.6 is a Canon-produced wide-angle to mid telephoto zoom lens for digital single-lens reflex cameras with an EF-S lens mount. The field of view has a 35 mm equivalent focal length of 28.8–88mm, and it is a standard kit lens on Canon's consumer APS-C DSLRs.
The f/5.6 FL-F was the first interchangeable lens to use calcium fluoride (CaF 2) on its lens elements to achieve extremely high contrast correcting chromatic aberration. It used two fluorite elements. The main benefits of fluorite on lens is its low index of refraction and low dispersion is superior to that of optical glass.
1: Imaging by a lens with chromatic aberration. 2: A lens with less chromatic aberration. In optics, aberration is a property of optical systems, such as lenses, that causes light to be spread out over some region of space rather than focused to a point. [1]
The 17–55 suffers from vignetting at f / 2.8 of 0.5–1 EV throughout the focal range, [3] [4] though current Canon bodies are able to correct this by storing the vignetting data within the camera memory. Chromatic aberration is a relative weakness at the wide end (at the edges and corners), [3] but is quite low for a zoom lens in this range. [4]