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Electronics Information Photography lighting equipment
| Photography lighting equipment |
| Tuesday, 30 January 2007 | |
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A wide variety of different studio lighting systems have been developed to provide desired lighting of an object to be photographed. An artificial lighting system generally comprises a dominant source of light and additional subsidiary sources of light, depending upon the configuration of the object. These sources of light may be obtained from a direct light or lights from variously positioned reflectors. Artificial illumination includes direct lighting, indirect lighting, and a variety of light reflectors, flash units, windows, and other light sources are employed to achieve the desired result. Such illumination devices are usually provided to, selectively, provide direct or indirect illumination of the scenes or objects to be photographed or recorded. In operation, such light fixtures have light output directed in a predetermined direction. The most common lighting systems in film, commercial, and photographic settings use either incandescent or fluorescent light elements. Typically, incandescent or fluorescent lighting systems are designed to be placed off to the side of the camera, or above or below the camera. Incandescent lights have been employed in lighting systems in which they have been arranged in various configurations, including on ring-shaped mounting frames. A major drawback of incandescent lighting systems is the amount of heat generating by the incandescent bulbs. Fluorescent lighting systems generate much less heat than incandescent lighting systems, but nevertheless are often large and cumbersome. Fluorescent bulbs are generally tube-shaped, which can limit the lighting configuration or mounting options. Circular fluorescent bulbs are also commercially available, and have been used in the past for motion picture lighting. Because of their custom nature, both incandescent lighting systems and fluorescent lighting systems can be difficult to adapt to different or changing needs of a particular film project or shoot. To solve the above-mentioned problem, light emitting diode (LED) devices have been used in photographic illumination apparatuses. A light emitting diode generates only a small amount of light energy and emits light whose spectrum has its peak in a low-sensitivity wavelength region of the sensitized material so as to eliminate the need for the filter. Flash lamps are essential in underwater photography both because red light is more easily absorbed by water to cause a color imbalance and because there is usually not enough natural light available. In standard photography, a light source produces illumination of specified intensity and specified spectral characteristics in order to produce the desired photographic exposure. For necessity of proper exposure and desired effect, light sources of mixed type, intensity, and duration are employed, simultaneously or sequentially. When a predetermined subject is photographed, the background must appear on the snapshot without showing objectionable shadows cast by the subject. An electrical regulator is used to provide the desired stability of lamp voltage, and regulators are known which can accommodate variations in the amplitude or the frequency of the line voltage which powers the lamp. Light diffusion boxes, also known as "softboxes" have long been used by photographers and camera crews to provide diffused lighting on photographic subjects. Diffusive and reflective type lighting devices are important in table top photographs in order to diffuse the light and prevent flare. Flare reduces color saturation in the photograph, reduces sharpness, and reduces contrast of light-to-dark tonal values. In order to set up the simulation and final flash effects, lamps are mounted on stands and are adjusted as required. Each individual photograph or group of photographs generally requires a separate assembly of lamps, screens and other equipment to produce the particular effect. Light projectors for use in photography, including cold light projectors, are known in which a first light source is disposed in a housing and serves to illuminate the object to be exposed via light guides. Mirrors, lenses, filters etc. are disposed between this first light source, which may for example be a halogen lamp, and the light guides. |
