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Cosina Voigtländer
Cosina Voigtländer refers to photographic products manufactured by Cosina under the Voigtländer name since 1999. Cosina leases rights to the Voigtländer name from RINGFOTO GmbH & Co. ALFO Marketing KG in Germany. Cosina Voigtländer products have included 35mm film SLR and rangefinder camera bodies, and lenses for the M39 lens mount (Leica screw mount), M42 lens mount, Leica M mount, and other lens mounts. Cameras 35 mm Rangefinder * Bessa L * Bessa R * Bessa T * Bessa R2 * Bessa R2S * Bessa R2C * Bessa R2A * Bessa R3A * Bessa R2M * Bessa R3M * Bessa R4A * Bessa R4M Medium format rangefinder * Bessa III 35 mm SLR * Bessaflex TM * VSL 43 Lenses Cosina started producing cameras and lenses under the Voigtländer brand in 1999, when it introduced a new M39 mount body and lenses. It has since produced a prodigious variety of these lenses in M39x26, Leica M mount, Nikon S rangefinder mount (some fully usable with Contax RF bodies), and SLR mounts includin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nikon F-mount
The Nikon F-mount is a type of interchangeable lens mount developed by Nikon for its 35mm format single-lens reflex cameras. The F-mount was first introduced on the Nikon F camera in 1959, and features a three-lug bayonet mount with a 44mm throat and a flange to focal plane distance of 46.5mm. The company continues, with the 2020 D6 model, to use variations of the same lens mount specification for its film and digital SLR cameras. History The Nikon F-mount is one of only two SLR lens mounts (the other being the Pentax K-mount) which were not abandoned by their associated manufacturer upon the introduction of autofocus, but rather extended to meet new requirements related to metering, autofocus, and aperture control. The large variety of F-mount compatible lenses makes it the largest system of interchangeable flange-mount photographic lenses in history. Over 400 different Nikkor lenses are compatible with the system. The F-mount is also popular in scientific and industrial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cosina
is a manufacturer of high-end optical glass, optical precision equipment, cameras, video and electronic related equipment, based in Nakano, Nagano Prefecture, Japan. History Cosina is the successor to Nikō (or "Nikoh"), a company set up as a lens processing factory in February 1959, which was a pioneer in optical polishing and lens grinding in Japan. In 1966, it also started to manufacture 35 mm compact cameras and 8 mm cine cameras, and a year later started the manufacture of 35mm film SLR cameras; in 1968 it started a glass melting factory. Nikō changed its name to Cosina in 1973. (The first part of the name is a reference to the Koshi area within Nakano, where the founder came from; while the 'Na' represents Nakano.) The name Cosina has previously appeared on compact and SLR cameras for 135 film. The CS-2 and CS-3 SLRs were introduced in 1978, followed in 1980 by the CT-1, CT-7 (the world's first all—push-button SLR), CT-10 and CT-20, the CT-1G in 1982 and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Single-lens Reflex Camera
A single-lens reflex camera (SLR) is a camera that typically uses a mirror and prism system (hence "reflex" from the mirror's reflection) that permits the photographer to view through the lens and see exactly what will be captured. With twin lens reflex and rangefinder cameras, the viewed image could be significantly different from the final image. When the shutter button is pressed on most SLRs, the mirror flips out of the light path, allowing light to pass through to the light receptor and the image to be captured. History File:Hasselblad 1600F.jpg, Medium format SLR by Hasselblad (Model 1600F), Sweden File:Zenza BRONICA S2 with ZENZANON 100mm F2.8.JPG, Medium format SLR by Bronica (Model S2), Japan. Bronica's later model—the Bronica EC—was the first medium format SLR camera to use an electrically operated focal-plane shutter File:Asahiflex600.jpg, The 1952 ( Pentax) Asahiflex, Japan's first single-lens reflex camera. File:Contaflex BW 2.JPG, The Contaflex III a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentax K Mount
The Pentax K-mount, sometimes referred to as the "PK-mount", is a bayonet lens mount standard for mounting interchangeable photographic lenses to 35 mm single-lens reflex (SLR) cameras. It was created by Pentax in 1975, and has since been used by all Pentax 35 mm and digital SLRs and also the MILC Pentax K-01. A number of other manufacturers have also produced many K-mount lenses and K-mount cameras. Mounts The Pentax K-mount has undergone a number of evolutions over the years as new functionality has been added. In general, the term K-mount may refer to the original K-mount, or to all its variations. Originally designed by Zeiss for an alliance with Pentax, it was intended to be a common lens mount for a proposed series of cameras and lenses. However, the plan failed to work out and the two firms parted company amicably, but Pentax retained the lens mount and at least one Zeiss lens design for its own use. K-mount The original K-mount is a simple bayonet conn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspheric Lens
An aspheric lens or asphere (often labeled ''ASPH'' on eye pieces) is a lens (optics), lens whose surface profiles are not portions of a sphere or Cylinder (geometry), cylinder. In photography, a camera lens, lens assembly that includes an aspheric element is often called an aspherical lens. The asphere's more complex surface profile can reduce or eliminate spherical aberration and also reduce other Aberration in optical systems, optical aberrations such as Astigmatism (optical systems), astigmatism, compared to a simple lens. A single aspheric lens can often replace a much more complex multi-lens system. The resulting device is smaller and lighter, and sometimes cheaper than the multi-lens design. Aspheric elements are used in the design of multi-element wide-angle lens, wide-angle and fast normal lenses to reduce aberrations. They are also used in combination with reflective elements (catadioptric systems) such as the aspherical Schmidt corrector plate used in the Schmidt cameras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photographic Filter
In photography and cinematography, a filter is a camera accessory consisting of an optical filter that can be inserted into the optical path. The filter can be of a square or oblong shape and mounted in a holder accessory, or, more commonly, a glass or plastic disk in a metal or plastic ring frame, which can be screwed into the front of or clipped onto the camera lens. Filters modify the images recorded. Sometimes they are used to make only subtle changes to images; other times the image would simply not be possible without them. In monochrome photography, coloured filters affect the relative brightness of different colours; red lipstick may be rendered as anything from almost white to almost black with different filters. Others change the colour balance of images, so that photographs under incandescent lighting show colours as they are perceived, rather than with a reddish tinge. There are filters that distort the image in a desired way, diffusing an otherwise sharp image, ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diaphragm (optics)
In optics, a diaphragm is a thin opaque structure with an opening (aperture) at its center. The role of the diaphragm is to ''stop'' the passage of light, except for the light passing through the ''aperture''. Thus it is also called a stop (an aperture stop, if it limits the brightness of light reaching the focal plane, or a field stop or flare stop for other uses of diaphragms in lenses). The diaphragm is placed in the light path of a lens or objective, and the size of the aperture regulates the amount of light that passes through the lens. The centre of the diaphragm's aperture coincides with the optical axis of the lens system. Most modern cameras use a type of adjustable diaphragm known as an iris diaphragm, and often referred to simply as an iris. See the articles on aperture and f-number for the photographic effect and system of quantification of varying the opening in the diaphragm. Iris diaphragms versus other types A natural optical system that has a diaphragm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
F-number
In optics, the f-number of an optical system such as a camera lens is the ratio of the system's focal length to the diameter of the entrance pupil ("clear aperture").Smith, Warren ''Modern Optical Engineering'', 4th Ed., 2007 McGraw-Hill Professional, p. 183. It is also known as the focal ratio, f-ratio, or f-stop, and is very important in photography. It is a dimensionless number that is a quantitative measure of lens speed; increasing the f-number is referred to as '' stopping down''. The f-number is commonly indicated using a lower-case hooked f with the format ''N'', where ''N'' is the f-number. The f-number is the reciprocal of the relative aperture (the aperture diameter divided by focal length). Notation The f-number is given by: N = \frac \ where f is the focal length, and D is the diameter of the entrance pupil (''effective aperture''). It is customary to write f-numbers preceded by "", which forms a mathematical expression of the entrance pupil diameter i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Focal Length
The focal length of an optical system is a measure of how strongly the system converges or diverges light; it is the inverse of the system's optical power. A positive focal length indicates that a system converges light, while a negative focal length indicates that the system diverges light. A system with a shorter focal length bends the rays more sharply, bringing them to a focus in a shorter distance or diverging them more quickly. For the special case of a thin lens in air, a positive focal length is the distance over which initially collimated (parallel) rays are brought to a focus, or alternatively a negative focal length indicates how far in front of the lens a point source must be located to form a collimated beam. For more general optical systems, the focal length has no intuitive meaning; it is simply the inverse of the system's optical power. In most photography and all telescopy, where the subject is essentially infinitely far away, longer focal length (lower ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
