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Instant-return Mirror
In photography, the single-lens reflex camera (SLR) is provided with a mirror to redirect light from the picture taking lens to the viewfinder prior to releasing the shutter for composing and focusing an image. When the shutter is released, the mirror swings up and away allowing the exposure of the photographic medium and instantly returns after the exposure. No SLR camera before 1954 had this feature, although the mirror on some early SLR cameras was entirely operated by the force exerted on the shutter release and only returned when the finger pressure was released. The Asahiflex II, released by Japanese company Asahi (Pentax) in 1954, was the world's first SLR camera with an instant return mirror.Michael R. Peres (2013)''The Focal Encyclopedia of Photography'', page 779 Taylor & Francis Taylor & Francis Group is an international company originating in the United Kingdom that publishes books and academic journals. Its parts include Taylor & Francis, CRC Press, Routledge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Single-lens Reflex Camera
In photography, a single-lens reflex camera (SLR) is a type of camera that uses a mirror and prism system to allow photographers to view through the lens and see exactly what will be captured. SLRs became the dominant design for professional and consumer-level cameras throughout the late 20th century, offering interchangeable lenses, through-the-lens (TTL) metering, and precise framing. Originating in the 1930s and popularized in the 1960s and 70s, SLR technology played a crucial role in the evolution of modern photography. Although digital single-lens reflex (DSLR) cameras succeeded film-based models, the rise of Mirrorless camera, mirrorless cameras in the 2010s has led to a decline in SLR use and production. 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 and allows light to pass through to the light receptor and the im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viewfinder
In photography, a viewfinder is a device on a camera that a photographer uses to determine exactly where the camera is pointed, and approximately how much of that view will be photographed. A viewfinder can be mechanical (indicating only direction and approximate view), with simple optical components, with precision optics and optical functions, or a digital accessory device used with digital cameras. View camera, View camera These cameras had no separate viewfinder. The exact image (although upside-down and reversed left-right) was viewed on a ground glass installed either in a replaceable plateholder, or in a spring back where springs hold the ground glass at the focus plane until a photographic plateholder is slid in front of it. Spring backs usually had a flip-up cover protecting the ground glass. A black focusing cloth was used with larger models. Mechanical finders Later referred to as "sports finders", for many sports and newspaper applications optical viewfinders ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shutter (photography)
In photography, a shutter is a device that allows light to pass for a determined period, exposing photographic film or a photosensitive digital sensor to light in order to capture a permanent image of a scene. A shutter can also be used to allow pulses of light to pass outwards, as seen in a movie projector or a signal lamp. A shutter of variable speed is used to control exposure time of the film. The shutter is constructed so that it automatically closes after a certain required time interval. The speed of the shutter is controlled either automatically by the camera based on the overall settings of the camera, manually through digital settings, or manually by a ring outside the camera on which various timings are marked. Camera shutter Camera shutters can be fitted in several positions: * Leaf shutters are usually fitted within a lens assembly (''central shutter''), or more rarely immediately behind (''behind-the-lens shutter'') or, even more rarely, in front of a lens, and s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Focus (optics)
In geometrical optics, a focus, also called an image point, is a point where ray (optics), light rays originating from a point on the object vergence (optics), converge. Although the focus is conceptually a point, physically the focus has a spatial extent, called the circle of confusion, blur circle. This non-ideal focusing may be caused by optical aberration, aberrations of the imaging optics. Even in the absence of aberrations, the smallest possible blur circle is the Airy disc caused by diffraction from the optical system's aperture; diffraction is the ultimate limit to the light focusing ability of any optical system. Aberrations tend to worsen as the aperture diameter increases, while the Airy circle is smallest for large apertures. An image, or image point or region, is in focus if light from object points is converged almost as much as possible in the image, and defocus aberration, out of focus if light is not well converged. The border between these is sometimes define ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photography
Photography is the visual arts, art, application, and practice of creating images by recording light, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as photographic film. It is employed in many fields of science, manufacturing (e.g., photolithography), and business, as well as its more direct uses for art, film and video production, recreational purposes, hobby, and mass communication. A person who operates a camera to capture or take Photograph, photographs is called a photographer, while the captured image, also known as a photograph, is the result produced by the camera. Typically, a lens is used to focus (optics), focus the light reflected or emitted from objects into a real image on the light-sensitive surface inside a camera during a timed Exposure (photography), exposure. With an electronic image sensor, this produces an Charge-coupled device, electrical charge at each pixel, which is Image processing, electro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asahiflex IIB
The Asahiflex was a 35 mm single-lens reflex camera built by the Asahi Optical Corporation (later to become Pentax). Asahi Optical introduced its first 35 mm camera in 1952. Unlike the majority of Japanese camera manufacturers of the time, Asahi made a conscious decision not to produce a mere German rangefinder copy, a relatively simple task. Instead, Asahi decided to copy the Praktiflex, a 1939 design, made in the German Democratic Republic. Asahi's designers (Nobuyuki Yoshida and Ryohei Suzuki) were convinced of the inherent superiority of the SLR and so proceeded along these lines. This effort resulted in the Asahiflex I, which was also the first Japanese 35 mm SLR. ''Note: According to company information from Asahi Optical Co., however, the Asahiflex I is based on Mr. Matsumoto’s Kochmann Reflex-Korelle, a pre-war 6x6 roll film camera.'' Asahiflex I The Asahiflex I had a non-interchangeable waist-level viewfinder, with a direct optical viewfinder for eye-level use. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentax
was a Japanese camera and optical equipment manufacturer. Currently, it exists as the Pentax Life Care Business Division of Hoya's medical endoscope business, as well as the digital camera brand of Ricoh Imaging, a subsidiary of Ricoh. Pentax, founded in 1919 as a town workshop specializing in polishing eyeglass lenses, developed Japan's first single-lens reflex camera, the Asahiflex, in 1952. By 2006, Pentax's domestic market share in digital cameras had declined to 4%. In 2007, Pentax was acquired by Hoya and subsequently merged with the company the following year. In 2011, Hoya spun off the Pentax brand's digital camera business, which was then acquired by Ricoh, leading to the establishment of Pentax Ricoh Imaging (current Ricoh Imaging). As a response to growing interest in film photography, Pentax launched the Pentax 17 on June 17, 2024. The Pentax 17 is a half-frame film camera. This launch marks the first Pentax film camera in over two decades. Corporate history ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taylor & Francis
Taylor & Francis Group is an international company originating in the United Kingdom that publishes books and academic journals. Its parts include Taylor & Francis, CRC Press, Routledge, F1000 (publisher), F1000 Research and Dovepress. It is a division of Informa, a United Kingdom-based publisher and conference company. Overview Founding The company was founded in 1852 when William Francis (chemist), William Francis joined Richard Taylor (editor), Richard Taylor in his publishing business. Taylor had founded his company in 1798. Their subjects covered agriculture, chemistry, education, engineering, geography, law, mathematics, medicine, and social sciences. Publications included the ''Philosophical Magazine''. Francis's son, Richard Taunton Francis (1883–1930), was sole partner in the firm from 1917 to 1930. Acquisitions and mergers In 1965, Taylor & Francis launched Wykeham Publications and began book publishing. T&F acquired Hemisphere Publishing in 1988, and the compa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
135 Film Cameras
135 may refer to: *135 (number) *AD 135 *135 BC *135 film, better known as 35 mm film, is a format of photographic film used for still photography *135 (New Jersey bus), a New Jersey Transit bus route *135 Hertha 135 Hertha is an asteroid from the inner region of the asteroid belt, approximately in diameter. Discovered on 18 February 1874 by German–American astronomer Christian Peters at the Litchfield Observatory near Clinton, New York, it was name ..., a main-belt asteroid * Škoda 135, a small family car {{numberdis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Single-lens Reflex Cameras
In photography, a single-lens reflex camera (SLR) is a type of camera that uses a mirror and prism system to allow photographers to view through the lens and see exactly what will be captured. SLRs became the dominant design for professional and consumer-level cameras throughout the late 20th century, offering interchangeable lenses, through-the-lens (TTL) metering, and precise framing. Originating in the 1930s and popularized in the 1960s and 70s, SLR technology played a crucial role in the evolution of modern photography. Although digital single-lens reflex (DSLR) cameras succeeded film-based models, the rise of Mirrorless camera, mirrorless cameras in the 2010s has led to a decline in SLR use and production. 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 and allows light to pass through to the light receptor and the im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
