HOME
*



picture info

Selenium Meter
A selenium meter is a light-measuring instrument based on the photoelectric properties of selenium. The most common use of such light meters is measuring the exposure value for photography. The electric part of such a meter is an electromagnetic measuring instrument which is connected to the anode and cathode of a selenium photo cell that produces more or less electric power when exposed to more or less light. The optical part of such a meter is a window in front of the photo cell's light-sensitive side. The window's surface is usually structured like a honeycomb made of convex lenses. This type of window helps to bundle the light coming from the direction in which the photo cell is pointed. The mechanical part of a selenium meter is an analog calculator which accepts exposure value and film speed as input parameters for showing the possible aperture and shutter-speed combinations for correct exposure. Types of meters Match-needle meters Uncoupled meter The simplest type of ma ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Film Sensitivity
A film also called a movie, motion picture, moving picture, picture, photoplay or (slang) flick is a work of visual art that simulates experiences and otherwise communicates ideas, stories, perceptions, feelings, beauty, or atmosphere through the use of moving images. These images are generally accompanied by sound and, more rarely, other sensory stimulations. The word "cinema", short for cinematography, is often used to refer to filmmaking and the film industry, and to the art form that is the result of it. Recording and transmission of film The moving images of a film are created by photographing actual scenes with a motion-picture camera, by photographing drawings or miniature models using traditional animation techniques, by means of CGI and computer animation, or by a combination of some or all of these techniques, and other visual effects. Before the introduction of digital production, series of still images were recorded on a strip of chemically sensitiz ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Rangefinder Camera
A rangefinder camera is a camera fitted with a rangefinder, typically a split-image rangefinder: a range-finding focusing mechanism allowing the photographer to measure the subject distance and take photographs that are in sharp focus. Most varieties of rangefinder show two images of the same subject, one of which moves when a calibrated wheel is turned; when the two images coincide and fuse into one, the distance can be read off the wheel. Older, non-coupled rangefinder cameras display the focusing distance and require the photographer to transfer the value to the lens focus ring; cameras without built-in rangefinders could have an external rangefinder fitted into the accessory shoe. Earlier cameras of this type had separate viewfinder and rangefinder windows; later the rangefinder was incorporated into the viewfinder. More modern designs have rangefinders coupled to the focusing mechanism so that the lens is focused correctly when the rangefinder images fuse; compare with the ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Heinz Waaske
Heinz Waaske (1924 – 1995) was a German camera designer, notably father of the Rollei 35. Early career Born in Berlin, Heinz Waaske started his career as a precision mechanic apprentice at Telefunken in Sickingenstraße in Berlin, where he studied from 1939 to 1942. After serving in the German army during World War II, being severely wounded and taken prisoner, he joined Krenzin in Berlin-Kreuzberg. There he encountered camera technology for the first time, and developed a great taste for it. For financial reasons, he could not study engineering. He started designing a 16mm miniature camera in his spare time, and sold the prototype in 1948 for 3.000 Marks. Work with Wirgin From 1948, Waaske transferred to the Wirgin brothers company in Wiesbaden. He worked as a precision mechanic and soon rose to head of the prototype workshop, to technical designer, and eventually to chief designer. He first improved the medium format 6x9 cameras, allowing cheaper manufacturing proc ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Leica III Lightmeter IMG 0310
Leica Camera AG () is a German company that manufactures cameras, optical lenses, photographic lenses, binoculars, rifle scopes and microscopes. The company was founded by Ernst Leitz in 1869 (Ernst Leitz Wetzlar), in Wetzlar, Germany. In 1986, the Leitz company changed its name to Leica, due to the fame of the Leica trade-name. The name Leica is derived from the first three letters of the founder's surname (Leitz) and the first two of the word camera: lei-ca (LEItz CAmera). At this time, Leica relocated its factory from Wetzlar to the nearby town of Solms. Leica Camera AG is 55% owned by Austrian investment firm ACM Projektentwicklung GmbH, and 45% owned by The Blackstone Group which licenses the Leica brand name from the Danaher Corporation-owned Leica Microsystems GmbH. History From the year 1907 to the 1950s, the buildings that formed Leica factory were built on Ernst Leitz Street in Wetzlar, and remained until 1986, when the factory was moved to the city of Solms. ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

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. A closely related ISO system is used to describe the relationship between exposure and output image lightness in digital cameras. Relatively insensitive film, with a correspondingly lower speed index, requires more exposure to light to produce the same image density as a more sensitive film, and is thus commonly termed a ''slow film''. Highly sensitive films are correspondingly termed ''fast films''. In both digital and film photography, the reduction of exposure corresponding to use of higher sensitivities generally leads to reduced image quality (via coarser film grain or higher image noise of other types). In short, the higher the sensitivity, the grainier the image will be. Ultimately sensitivity is limited by the quantum efficiency of the film or sensor. Film speed measurement systems His ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Zenit (camera)
Zenit (russian: Зени́т) is a Russian (and formerly Soviet) camera brand manufactured by KMZ in the town of Krasnogorsk near Moscow since 1952 and by BelOMO in Belarus since the 1970s. The Zenit trademark is associated with 35 mm SLR cameras. Among related brands are Zorki for 35 mm rangefinder cameras, Moskva (Moscow) and Iskra for medium-format folding cameras and Horizon for panoramic cameras. In the 1960s and 1970s, they were exported by Mashpriborintorg to 74 countries. The name is sometimes spelled Zenith in English, such as the manuals published by the UK Zenit-importer TOE. However, TOE's imported camera bodies as from 1963 retained the "Zenit" badges. The early Zorki-based models before that time were labelled "Zenith" in a handwritten style of script. Digital models During the 2018 Photokina expo, Zenit announced that it was resuming camera and lens production for the M-mount, as well as for unspecified Nikon and Canon mounts in 2019. Zenit M The ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Photoelectric
The photoelectric effect is the emission of electrons when electromagnetic radiation, such as light, hits a material. Electrons emitted in this manner are called photoelectrons. The phenomenon is studied in condensed matter physics, and solid state and quantum chemistry to draw inferences about the properties of atoms, molecules and solids. The effect has found use in electronic devices specialized for light detection and precisely timed electron emission. The experimental results disagree with classical electromagnetism, which predicts that continuous light waves transfer energy to electrons, which would then be emitted when they accumulate enough energy. An alteration in the intensity of light would theoretically change the kinetic energy of the emitted electrons, with sufficiently dim light resulting in a delayed emission. The experimental results instead show that electrons are dislodged only when the light exceeds a certain frequency—regardless of the light's intensity or ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Math Needle Meter
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics with the major subdisciplines of number theory, algebra, geometry, and analysis, respectively. There is no general consensus among mathematicians about a common definition for their academic discipline. Most mathematical activity involves the discovery of properties of abstract objects and the use of pure reason to prove them. These objects consist of either abstractions from nature orin modern mathematicsentities that are stipulated to have certain properties, called axioms. A ''proof'' consists of a succession of applications of deductive rules to already established results. These results include previously proved theorems, axioms, andin case of abstraction from naturesome basic properties that are considered true starting points of t ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]