|
Voigtländer Prominent
Prominent refers to two distinct lines of rangefinder cameras made by Voigtländer. The first Prominent, stylized in all-caps as PROMINENT and also known as the Prominent 6×9 to distinguish it from the later camera line, was a folding, fixed-lens rangefinder camera that used 120 film and was first marketed in 1932. Relatively few were sold and the post-war Prominent, using 135 film, is better known. The second Prominent (stylized with small caps as ) was a line of 35mm interchangeable lens cameras built after World War II in the 1950s, equipped with leaf shutters. The second line of Prominent cameras were marketed as professional system cameras against the Leica threadmount and M bayonet mount and Zeiss Ikon Contax rangefinder camera lines. Voigtländer also sold the Voigtländer Vitessa, Vitessa and Voigtländer Vito, Vito lines of compact 35mm rangefinders contemporaneously, generally equipped with fixed, collapsible normal lenses, as less-expensive alternatives to the Promin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Double-Gauss Lens
The double Gauss lens is a compound lens used mostly in camera lenses that reduces optical aberrations over a large focal plane. Design The earliest double Gauss lens, patented by Alvan Graham Clark in 1888, consists of two symmetrically-arranged Gauss lenses. Each Gauss lens is a two-element achromatic lens with a positive meniscus lens on the object side and a negative meniscus lens on the image side. In Clark's symmetric arrangement, this makes four elements in four groups: two positive meniscus lenses on the outside with two negative meniscus lenses inside them. The symmetry of the system and the splitting of the optical power into many elements reduces the optical aberrations within the system. There are many variations of the design. Sometimes extra lens elements are added. The basic lens type is one of the most developed and used photographic lenses. The design forms the basis for many camera lenses in use today, especially the wide-aperture standard lenses used with 35 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Voigtländer Bessa
Bessa is the best-known line of folding camera, folding viewfinder and rangefinder cameras manufactured by Voigtländer, which was a dual-format camera that took 6×9 and 4.5×6 pictures on medium format 120 film, rollfilm. The Bessa was introduced in 1929 and an improved version incorporating a coupled rangefinder was introduced as the Bessa Rangefinder in 1935; the line was supplemented by the single-format Baby Bessa (aka ''Bessa 46'' and ''Bessa 66''), which took 4.5×6 and 6×6 pictures, respectively. Production was interrupted by World War II; after the war, the Bessa resumed limited production, but was succeeded by the Bessa I and Bessa II (both 1950), the latter including a rangefinder. Similar rollfilm cameras manufactured contemporaneously by Voigtländer included the Petito (1924), Rollfilm (1925), Inos (1931), Jubilar (1931), Prominent (1932), and Perkeo (1950, 6×6). In 1997, the Voigtländer brand was licensed to Cosina, which subsequently introduced an unrelated line ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aperture
In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image of the aperture and focal length of an optical system determine the cone angle of a bundle of rays that comes to a focus in the image plane. An optical system typically has many structures that limit ray bundles (ray bundles are also known as ''pencils'' of light). These structures may be the edge of a lens or mirror, or a ring or other fixture that holds an optical element in place or may be a special element such as a diaphragm placed in the optical path to limit the light admitted by the system. In general, these structures are called stops, and the aperture stop is the stop that primarily determines the cone of rays that an optical system accepts (see entrance pupil). As a result, it also determines the ray cone angle and brightne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Focal Length
The focal length of an Optics, optical system is a measure of how strongly the system converges or diverges light; it is the Multiplicative inverse, inverse of the system's optical power. A positive focal length indicates that a system Convergence (optics), converges light, while a negative focal length indicates that the system Divergence (optics), diverges light. A system with a shorter focal length bends the Ray (optics), 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 beam, collimated (parallel) rays are brought to a Focus (optics), 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 mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Voigtlander Prominent II
Voigtländer () was a significant long-established company within the optics and photographic industry, headquartered in Braunschweig, Germany, and today continues as a trademark for a range of photographic products. History Voigtländer was founded in Vienna, Archduchy of Austria, in 1756, by . Voigtländer produced mathematical instruments, precision mechanical products, optical instruments, including optical measuring instruments and opera glasses, and is the oldest name in cameras. Early beginnings Johann Christoph Voigtländer (November 19, 1732 in Leipzig – June 27, 1797 in Vienna), the son of a carpenter, came to Prague in 1755, and to Vienna in the same year, and worked from 1757 to 1762 in the workshop of Meinicke, who produced mathematical instruments. Through Johann Voigtländer's skilful achievements, the Minister of State of the Habsburg monarchy— Prince Wenzel von Kaunitz, drew attention to Voigtländer and Empress Maria Theresa of Austria granted Voigtlä ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shutter Speed
In photography, shutter speed or exposure time is the length of time that the film or digital sensor inside the camera is exposed to light (that is, when the camera's shutter (photography), shutter is open) when taking a photograph. The amount of light that reaches the Photographic film, film or image sensor is proportional to the exposure time. of a second will let half as much light in as . Introduction The camera's shutter speed, the lens's aperture or f-stop, and the scene's luminance together determine the amount of light that reaches the film or sensor (the exposure (photography), exposure). Exposure value (EV) is a quantity that accounts for the shutter speed and the f-number. Once the sensitivity to light of the recording surface (either film or sensor) is set in numbers expressed in "Film speed#ISO, ISOs" (e.g. 200 ISO, 400 ISO), the light emitted by the scene photographed can be controlled through aperture and shutter-speed to match the film or sensor sensitivit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aperture
In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image of the aperture and focal length of an optical system determine the cone angle of a bundle of rays that comes to a focus in the image plane. An optical system typically has many structures that limit ray bundles (ray bundles are also known as ''pencils'' of light). These structures may be the edge of a lens or mirror, or a ring or other fixture that holds an optical element in place or may be a special element such as a diaphragm placed in the optical path to limit the light admitted by the system. In general, these structures are called stops, and the aperture stop is the stop that primarily determines the cone of rays that an optical system accepts (see entrance pupil). As a result, it also determines the ray cone angle and brightne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Meter
A light meter (or illuminometer) is a device used to measure the amount of light. In photography, an exposure meter is a light meter coupled to either a Digital data, digital or analog calculator which displays the correct shutter speed and f-number for optimum exposure (photography), exposure, given a certain lighting situation and film speed. Similarly, exposure meters are also used in the fields of cinematography and scenic design, in order to determine the optimum light level for a scene. Light meters also are used in the general field of architectural lighting design to verify proper installation and performance of a building lighting system, and in assessing the light levels for growing plants. If a light meter is giving its indications in luxes, it is called a "luxmeter". Evolution File:Watkins Bee Meter.jpg, Watkins Bee Meter - a type of actinometer File:Leudi extinction meter.jpg, Leudi extinction meter File:METROPHOT.jpg, Metrophot Norwood Director IMG2024062813453 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compur
Friedrich Deckel GmbH, also known as F.Deckel, was a German company founded by Friedrich Deckel and Christian Bruns in Munich as Bruns & Deckel in 1903. Its most famous product is the ''Compur'' line of leaf shutters used on many photographic lenses starting from 1911. Bruns and Deckel previously had worked together at C. A. Steinheil & Söhne; Bruns was an inventor responsible for developing leaf shutters while Deckel was a laboratory mechanic. Corporate history By 1910, Zeiss had acquired a 16.8% stake in F.Deckel. Zeiss also owned a significant portion of competitor (AGC), which was later renamed Prontor after its competing leaf shutter. Taking advantage of their growing knowledge of factory production methods and machinery, by about 1920 Deckel started producing "extra" machines for sale to the trade, most notably the versatile ''FP'' line of industrial milling machines. During World War II, photographic equipment production was paused and F.Deckel made fuel pumps for BMW ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macro Photography
Macro photography (or photomacrography or macrography, and sometimes macrophotography) is extreme close-up photography, usually of very small subjects and living organisms like insects, in which the size of the subject in the photograph is greater than life-size (though ''macrophotography'' also refers to the art of making very large photographs). By the original definition, a macro photograph is one in which the size of the subject on the negative or image sensor is life-size or greater. In some senses, however, it refers to a finished photograph of a subject that is greater than life-size. The ratio of the subject size on the film plane (or sensor plane) to the actual subject size is known as the reproduction ratio. Likewise, a macro lens is classically a lens capable of reproduction ratios of at least 1:1, although it often refers to any lens with a large reproduction ratio, despite rarely exceeding 1:1. Apart from technical photography and film-based processes, where th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Close-up Lens
In photography, a close-up lens (sometimes referred to as ''close-up filter'' or a ''macro filter'') is a simple secondary lens used to enable macro photography without requiring a specialised primary lens. They work like reading glasses, allowing a primary lens to focus more closely. Bringing the focus closer allows the photographer more possibilities. Close-up lenses typically mount on the filter thread of the primary lens, and are often manufactured and sold by suppliers of photographic filters. Nonetheless, they are lenses and not photographic filter, filters. Some manufacturers refer to their close-up lenses as ''diopters'', after the unit of measurement of their optical power. Close-up lenses do not affect exposure, unlike extension tubes, which also can be used for macro photography with a non-macro lens. Optical power Close-up lenses are often specified by their optical power in diopters, the reciprocal of the focal length in meters. For a close-up lens, the diopter v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
