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Long Focus Lens
In photography, a long-focus lens is a camera lens which has a focal length that is longer than the diagonal measure of the film or sensor that receives its image. It is used to make distant objects appear magnification, magnified with magnification increasing as longer focal length lenses are used. A long-focus lens is one of three basic photographic lens types classified by relative focal length, the other two being a normal lens and a wide-angle lens. As with other types of camera lenses, the focal length is usually expressed in a millimeter value written on the lens, for example: a 500 mm lens. The most common type of long-focus lens is the telephoto lens, which incorporate a special lens group known as a ''telephoto group'' to make the physical length of the lens shorter than the focal length. Effects Long-focus lenses are best known for making distant objects appear magnification, magnified. This effect is similar to moving closer to the object, but is not the same, ...
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500mm Telephoto Lens 01
5 (five) is a number, numeral (linguistics), numeral and numerical digit, digit. It is the natural number, and cardinal number, following 4 and preceding 6, and is a prime number. Humans, and many other animals, have 5 Digit (anatomy), digits on their Limb (anatomy), limbs. Mathematics 5 is a Fermat prime, a Mersenne prime exponent, as well as a Fibonacci number. 5 is the first congruent number, as well as the length of the hypotenuse of the smallest integer-sided right triangle, making part of the smallest Pythagorean triple (3, 4, 5). 5 is the first safe prime and the first good prime. 11 forms the first pair of sexy primes with 5. 5 is the second Fermat number, Fermat prime, of a total of five known Fermat primes. 5 is also the first of three known Wilson primes (5, 13, 563). Geometry A shape with five sides is called a pentagon. The pentagon is the first regular polygon that does not Tessellation, tile the Plane (geometry), plane with copies of itself. It is the ...
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135 Film
file:135film.jpg, 135 film. The film is wide. Each image is 24×36 mm in the most common "small film" format (sometimes called "double-frame" for its relationship to the "single-frame" 35 mm movie format or full frame after the introduction of 135 sized digital sensors; confusingly, "full frame" was also used to describe the Full frame (cinematography), full gate of the movie format half the size). file:LEI0060 186 Leica I Sn.5193 1927 Originalzustand Front-2 FS-15.jpg, Leica I, 1927, the first successful camera worldwide for 35 cine film 135 film, more popularly referred to as 35 mm film or 35 mm, is a format of photographic film with a film gauge of loaded into a standardized type of magazine (also referred to as a cassette or cartridge) for use in 135 film cameras. The term 135 was introduced by Kodak in 1934 as a designation for 35 mm film specifically for still photography, perforated with Kodak Standard perforations. It quickly grew in populari ...
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Film Speed
Film speed is the measure of a photographic film's sensitivity to light, determined by sensitometry and measured on various numerical scales, the most recent being the ISO system introduced in 1974. A closely related system, also known as ISO, is used to describe the relationship between exposure and output image lightness in digital cameras. Prior to ISO, the most common systems were ASA in the United States and DIN in Europe. The term ''speed'' comes from the early days of photography. Photographic emulsions that were more sensitive to light needed less time to generate an acceptable image and thus a complete exposure could be finished faster, with the subjects having to hold still for a shorter length of time. Emulsions that were less sensitive were deemed "slower" as the time to complete an exposure was much longer and often usable only for still life photography. Exposure times for photographic emulsions shortened from hours to fractions of a second by the late 19th ...
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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 ...
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Lens Mount
A lens mount is an interface – mechanical and often also electrical – between a photographic camera body and a lens. It is a feature of camera systems where the System camera, body allows interchangeable lenses, most usually the rangefinder camera, single lens reflex type, single lens mirrorless type or any movie camera of 16 mm or higher film gauge, gauge. Lens mounts are also used to connect optical components in instrumentation that may not involve a camera, such as the modular components used in optical laboratory prototyping which join via C mount, C-mount or T-mount elements. Mount types A lens mount may be a screw-threaded type, a Bayonet#Linguistic impact, bayonet-type, or a breech-lock (friction lock) type. Modern still camera lens mounts are of the bayonet type, because the bayonet mechanism precisely aligns mechanical and electrical features between lens and body. Screw-threaded mounts are fragile and do not align the lens in a reliable rotational position, yet ...
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System Camera
A system camera or camera body is a camera with interchangeable components that constitutes the core of a system. Early representatives include Leica Camera, Leica I Schraubgewinde (1930), Exakta (1936) and the Nikon F (1959). System cameras are often Single-lens reflex camera, single-lens reflex (SLR) or Twin-lens reflex camera, twin-lens reflex (TLR) but can also be rangefinder cameras or, more recently, mirrorless interchangeable-lens cameras. Voice coil motors (VCMs) are used to control the lens movement to achieve fast and accurate autofocus. The VCM moves the lens elements to focus the light onto the sensor with high precision. Systems are usually named for the lens mount, such Nikon F-mount, Canon EF mount, and M42 lens mount, M42 mount (a non-proprietary mount using a screw thread). Even point-and-shoot cameras usually include a Tripod screw, tripod socket. A system camera includes at the very least a camera body and separate, interchangeable lenses, whence the alterna ...
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T-mount
The T-mount is a standard lens mount for cameras and other optical assemblies. The usual T-mount is a screw mount using a male 42×0.75 (42 mm diameter, 0.75 mm thread pitch) metric thread on the lens with a flange focal distance of 55 mm and a mating female 42mm thread on a camera adapter or other optical component. This thread form is referred to as T-thread. (This should not be confused with the M42 lens mount which is also 42 mm diameter, but has a 1 mm thread pitch. The T-thread is sometimes described as "M42×0.75," which is the usual manner in which to describe a metric thread.) The "T" is said to stand for Tamron or Taisei, a Japanese manufacturer that released in 1957 the first of a line of aftermarket camera lenses that fit 35 mm SLR cameras built by various manufacturers using their universal ''T-mount''. On the first model, the mini T-mount used a M37×0.75 thread; Tamron's canonical M42×0.75 T-thread didn't appear on the market until ...
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Eyepiece
An eyepiece, or ocular lens, is a type of lens that is attached to a variety of optical devices such as Optical telescope, telescopes and microscopes. It is named because it is usually the lens that is closest to the eye when someone looks through an optical device to observe an object or sample. The Objective (optics), objective lens or mirror collects light from an object or sample and brings it to focus creating an image of the object. The eyepiece is placed near the Focus (optics), focal point of the objective to magnify this image to the eyes. (The eyepiece and the eye together make an image of the image created by the objective, on the retina of the eye.) The amount of magnification depends on the focal length of the eyepiece. An eyepiece consists of several "Lens (optics), lens elements" in a housing, with a "barrel" on one end. The barrel is shaped to fit in a special opening of the instrument to which it is attached. The image can be focus (optics), focused by moving th ...
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Machine Vision
Machine vision is the technology and methods used to provide image, imaging-based automation, automatic inspection and analysis for such applications as automatic inspection, process control, and robot guidance, usually in industry. Machine vision refers to many technologies, software and hardware products, integrated systems, actions, methods and expertise. Machine vision as a systems engineering discipline can be considered distinct from computer vision, a form of computer science. It attempts to integrate existing technologies in new ways and apply them to solve real world problems. The term is the prevalent one for these functions in industrial automation environments but is also used for these functions in other environment vehicle guidance. The overall machine vision process includes planning the details of the requirements and project, and then creating a solution. During run-time, the process starts with imaging, followed by automated image analysis, analysis of the image a ...
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Surveillance
Surveillance is the monitoring of behavior, many activities, or information for the purpose of information gathering, influencing, managing, or directing. This can include observation from a distance by means of electronic equipment, such as closed-circuit television (CCTV), or interception of electronically transmitted information like Internet traffic. Increasingly, Government, governments may also obtain Customer data, consumer data through the purchase of online information, effectively expanding surveillance capabilities through commercially available digital records. It can also include simple technical methods, such as Human intelligence (intelligence gathering), human intelligence gathering and postal interception. Surveillance is used by citizens, for instance for protecting their neighborhoods. It is widely used by governments for intelligence gathering, including espionage, prevention of crime, the protection of a process, person, group or object, or the investigat ...
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Nature Photography
Nature photography encompasses a wide range of photography taken outdoors and devoted to displaying natural elements such as landscapes, wildlife, plants, and close-ups of natural scenes and textures. Nature photography tends to place a stronger emphasis on the aesthetic value of the photo than other photography genres, such as photojournalism and documentary photography.Purdue Univ."Nature and Landscape Photography", from ''Visualizing Nature: Promoting Public Understanding and Appreciation of Nature'', [Department of] Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, Indiana, retrieved October 4, 2015. "Nature photography" overlaps the fields of—and is sometimes considered an overarching category including—"wildlife photography", "landscape photography", and "garden photography". Nature photographs are published in scientific, travel and cultural magazines such as ''National Geographic Magazine'', ''National Wildlife Magazine'' and ''National Au ...
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Astrophotography
Astrophotography, also known as astronomical imaging, is the photography or imaging of astronomical objects, celestial events, or areas of the night sky. The first photograph of an astronomical object (the Moon) was taken in 1839, but it was not until the late 19th century that advances in technology allowed for detailed stellar photography. Besides being able to record the details of extended objects such as the Moon, Sun, and planets, modern astrophotography has the ability to image objects outside of the visible spectrum of the human eye such as dim stars, nebulae, and galaxy, galaxies. This is accomplished through long-exposure photography, long time exposure as both film and digital cameras can accumulate and sum photons over long periods of time or using specialized optical filters which limit the photons to a certain wavelength. Photography using extended exposure-times revolutionized the field of professional astronomical research, recording hundreds of thousands of new ...
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