|
Flash Gun
A flash is a device used in photography that produces a brief burst of light (lasting around of a second) at a color temperature of about 5500 K to help illuminate a scene. The main purpose of a flash is to illuminate a dark scene. Other uses are capturing quickly moving objects or changing the quality of light. ''Flash'' refers either to the flash of light itself or to the electronic flash unit discharging the light. Most current flash units are electronic, having evolved from single-use flashbulbs and flammable powders. Modern cameras often activate flash units automatically. Flash units are commonly built directly into a camera. Some cameras allow separate flash units to be mounted via a standardized accessory mount bracket (a '' hot shoe''). In professional studio equipment, flashes may be large, standalone units, or studio strobes, powered by special battery packs or connected to mains power. They are either synchronized with the camera using a flash synchronization ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adolf Miethe
Adolf Miethe (; 25 April 1862, Potsdam – 5 May 1927, Berlin) was a German scientist, lens designer, photochemistry, photochemist, photographer, author and educator. He co-invented the first practical photographic Flash (photography), flash and made important contributions to the progress of practical color photography. Early life Adolf Miethe grew up in a middle-class family. His father was a chocolate manufacturer and city councillor in Potsdam. After studying physics, chemistry and astronomy in Berlin, he moved to Göttingen, where in 1889 he received his doctorate for a thesis on the actinometry of photographic astronomic fixed star exposures. Career In 1887 he co-invented (with Johannes Gaedicke) the photographic magnesium powder flash-light. After earning his doctorate, he worked for Edmund Hartnack's optical workshop in Potsdam designing microscope objectives. In 1891, after the death of Hartnack, he moved to Rathenow and took a job with the optical company Schulze & Barth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brownie (camera)
The Brownie was a series of camera models made by Eastman Kodak and first released in 1900. It introduced the Snapshot (photography), snapshot to the masses by addressing the cost factor which had meant that amateur photography remained beyond the means of many people; the Pocket Kodak, for example, would cost most families in Britain nearly a whole month's wages. The Brownie was a basic Paperboard, cardboard box camera with a simple Lens (optics)#Types of simple lenses, convex-concave lens that took -inch square pictures on No. 117 roll film. It was conceived and marketed for sales of Kodak roll films. Because of its simple controls and initial price of US$1 (equivalent to $ in ) along with the low price of Kodak roll film and processing, the Brownie camera surpassed its marketing goal. Invention and etymology The Brownie was invented by Frank A. Brownell for the Eastman Kodak Company. Named after The Brownies, the Brownie characters popularised by the Canadian writer Palmer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the world's countries participated, with many nations mobilising all resources in pursuit of total war. Tanks in World War II, Tanks and Air warfare of World War II, aircraft played major roles, enabling the strategic bombing of cities and delivery of the Atomic bombings of Hiroshima and Nagasaki, first and only nuclear weapons ever used in war. World War II is the List of wars by death toll, deadliest conflict in history, causing World War II casualties, the death of 70 to 85 million people, more than half of whom were civilians. Millions died in genocides, including the Holocaust, and by massacres, starvation, and disease. After the Allied victory, Allied-occupied Germany, Germany, Allied-occupied Austria, Austria, Occupation of Japan, Japan, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bayonet Mount
A bayonet mount (mainly as a method of mechanical attachment, such as fitting a lens to a camera using a matching lens mount) or bayonet connector (for electrical use) is a fastening mechanism consisting of a cylindrical male side with one or more radial pegs, and a female receptor with matching L-shaped slot(s) and with spring(s) to keep the two parts locked together. The slots are shaped like a capital letter L with serif (a short upward segment at the end of the horizontal arm); the peg slides into the vertical arm of the L, rotates across the horizontal arm, then is pushed slightly upwards into the short vertical "serif" by the spring; the connector is no longer free to rotate unless pushed down against the spring until the peg is out of the "serif". The bayonet mount is the standard light bulb fitting in the United Kingdom and in many countries that were members of the British Empire including Australia, Hong Kong, Fiji, India, Pakistan, Sri Lanka, Ireland and New Zea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Twin-lens Reflex Camera
A twin-lens reflex camera (TLR) is a type of camera with two objective Photographic lens, lenses of the same focal length. One of the lenses is the photographic objective or "taking lens" (the lens that takes the picture), while the other is used for the viewfinder system, which is usually viewed from above at waist level. In addition to the objective, the viewfinder consists of a 45-degree mirror (the reason for the word ''reflex'' in the name), a matte focusing screen at the top of the camera, and a pop-up hood surrounding it. The two objectives are connected, so that the focus shown on the focusing screen will be exactly the same as on the film. However, many inexpensive "pseudo" TLRs are fixed-focus models to save on the mechanical complexity. Most TLRs use Shutter (photography)#Diaphragm shutter, leaf shutters with shutter speeds up to 1/500 of a second with a Bulb (photography), bulb setting. For practical purposes, all TLRs are film cameras, most often using 120 film, alt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Press Camera
A press camera is a medium or large format view camera that was predominantly used by press photographers in the early to mid-20th century. It was largely replaced for press photography by 35mm film cameras in the 1960s, and subsequently, by digital cameras. The quintessential press camera was the Speed Graphic. Press cameras are still used as portable and rugged view cameras. Details Press cameras were widely used from the 1900s through the early 1960s and commonly have the following features: * collapsible into strong, compact boxes * flexible bellows, attached to a flatbed track * easily interchangeable lenses, mounted on a solid support * ability to accept sheet film, film packs, and roll film, through the use of interchangeable film backs and holders * ground glass focusing screen * optical viewfinder * handheld operation * reduced number, reduced range or absence of movements, in contrast to field cameras or other view camera formats * optical rangefinder focusi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flash Synchronization
In photography, flash synchronization or flash sync is the synchronizing the firing of a photographic flash with the opening of the shutter admitting light to photographic film or electronic image sensor. In cameras with mechanical (clockwork) shutters synchronization is supported by an electrical contact within the shutter mechanism, which closes the circuit at the appropriate moment in the shutter opening process. In electronic digital cameras, the mechanism is usually a programmable electronic timing circuit, which may, in some cameras, take input from a mechanical shutter contact. The flash is connected electrically to the camera either by a cable with a standardized coaxial PC (for Prontor/Compur) connector (as defined in ISO 519), or via contacts in an ''accessory mount'' ( hot shoe) bracket. Faster shutter speeds are often better when there is significant ambient illumination, and flash is used to flash fill subjects that are backlit without motion blur, or to in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zirconium
Zirconium is a chemical element; it has Symbol (chemistry), symbol Zr and atomic number 40. First identified in 1789, isolated in impure form in 1824, and manufactured at scale by 1925, pure zirconium is a lustrous transition metal with a greyish-white color that closely resembles hafnium and, to a lesser extent, titanium. It is solid at room temperature, Ductility, ductile, malleable and corrosion-resistant. The name ''zirconium'' is derived from the name of the mineral zircon, the most important source of zirconium. The word is related to Persian Language, Persian ''Jargoon, zargun'' (zircon; ''zar-gun'', "gold-like" or "as gold"). Besides zircon, zirconium occurs in over 140 other minerals, including baddeleyite and eudialyte; most zirconium is produced as a byproduct of minerals mined for titanium and tin. Zirconium forms a variety of inorganic chemistry, inorganic compounds, such as zirconium dioxide, and organometallic compounds, such as zirconocene dichloride. Five isotope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colour Film
Color photography (also spelled as colour photography in Commonwealth English) is photography that uses media capable of capturing and reproducing colors. By contrast, black-and-white or gray-monochrome photography records only a single channel of luminance (brightness) and uses media capable only of showing shades of gray. In color photography, electronic sensors or light-sensitive chemicals record color information at the time of exposure. This is usually done by analyzing the spectrum of colors into three channels of information, one dominated by red, another by green and the third by blue, in imitation of the way the normal human eye senses color. The recorded information is then used to reproduce the original colors by mixing various proportions of red, green and blue light ( RGB color, used by video displays, digital projectors and some historical photographic processes), or by using dyes or pigments to remove various proportions of the red, green and blue which are pre ... [...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] |
Oxygen
Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), nonmetal, and a potent oxidizing agent that readily forms oxides with most elements as well as with other chemical compound, compounds. Oxygen is abundance of elements in Earth's crust, the most abundant element in Earth's crust, making up almost half of the Earth's crust in the form of various oxides such as water, carbon dioxide, iron oxides and silicates.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. It is abundance of chemical elements, the third-most abundant element in the universe after hydrogen and helium. At standard temperature and pressure, two oxygen atoms will chemical bond, bind covalent bond, covalently to form dioxygen, a colorless and odorless diatomic gas with the chemical formula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
