Lighting
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The incandescent light bulb, incandescent lamp or incandescent light globe creates light by heating a metal filament wire to a high temperature until it sparks. The spark is protected from air by a glass bulb that surrounds it. In a halogen light, a chemical process returns metal to the filament, enabling the light to last a lot longer than other lighting. The light bulb is supplied with electrical current by feed-through terminals or wires embedded in the glass. Most bulbs are used in a socket which provides mechanical support and electrical connections.
Incandescent Lighting
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Incandescent bulbs come in a variety of sizes, light output, and voltage ratings; they start at about1.5 volts to about 300 volts. They require no external regulating equipment, and also have a low manufacturing costs, and work equally well on either alternating current or direct current. For this reason, the incandescent lamp is used in households and commercial lighting, for portable lighting such as table lamps, car headlamps, and flashlights, and for decorative and advertising lighting.
Certain uses of the incandescent bulb use the heat generated by the filament, such as incubators, infrared heating for industrial heating and drying processes, and the Easy-Bake Oven toy. This waste heat increases the energy required by a building's air conditioning system.
Incandescent light bulbs are gradually being replaced in many applications by other types of electric lights, such as LEDs (light-emitting diodes), CCFL (cold cathode fluorescent lamps), high-intensity discharge lamps, and these newer technologies improve the ratio of visible light to heat generation. Some jurisdictions, such as the EU, are in the process decreasing the use of incandescent light bulbs in favor of more energy-efficient lighting.
History
In addressing the question of who invented the incandescent lamp, historians Robert Friedel and Paul Israel list 22 inventors of incandescent lamps prior to Joseph Swan and Thomas Edison. They conclude that Edison's version was able to outstrip the others because of a combination of three factors: an effective incandescent material, a higher vacuum than others were able to achieve (by use of the Sprengel pump) and a high opposition that made power distribution from a national source economically practical.
Certain uses of the incandescent bulb use the heat generated by the filament, such as incubators, infrared heating for industrial heating and drying processes, and the Easy-Bake Oven toy. This waste heat increases the energy required by a building's air conditioning system.
Incandescent light bulbs are gradually being replaced in many applications by other types of electric lights, such as LEDs (light-emitting diodes), CCFL (cold cathode fluorescent lamps), high-intensity discharge lamps, and these newer technologies improve the ratio of visible light to heat generation. Some jurisdictions, such as the EU, are in the process decreasing the use of incandescent light bulbs in favor of more energy-efficient lighting.
History
In addressing the question of who invented the incandescent lamp, historians Robert Friedel and Paul Israel list 22 inventors of incandescent lamps prior to Joseph Swan and Thomas Edison. They conclude that Edison's version was able to outstrip the others because of a combination of three factors: an effective incandescent material, a higher vacuum than others were able to achieve (by use of the Sprengel pump) and a high opposition that made power distribution from a national source economically practical.
Halogen lighting
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A halogen lamp, also known as a tungsten halogen lamp, is an incandescent lamp with a tungsten filament contained within an inactive gas and a small amount of a halogen such as iodine or bromine. The chemical halogen cycle redeposit evaporated tungsten back on to the filament, enabling the light life to last longer. Due to this, a halogen lamp can be operated at a much hotter temperature than a standard gas-filled lamp of similar power and operating life. This gives it an advanced luminous efficacy (10–30 lm/W). The lamp gives light of a higher color temperature. Because of their smaller size, halogen lamps can advantageously be used with optical systems that are more efficient in how they cast emitted light.
History
A carbon filament lamp using chlorine to prevent darkening of the envelope was patented in 1882, and chlorine-filled "NoVak" lamps were marketed in 1892. The use of iodine was proposed in a 1933 patent, which also described the cyclic redisposition of tungsten back on the filament. In 1959 General Electric patenteda practical lamp using iodine.
History
A carbon filament lamp using chlorine to prevent darkening of the envelope was patented in 1882, and chlorine-filled "NoVak" lamps were marketed in 1892. The use of iodine was proposed in a 1933 patent, which also described the cyclic redisposition of tungsten back on the filament. In 1959 General Electric patenteda practical lamp using iodine.
Hard light
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Hard light, like that found on a bright, sunny day, creates very bright and very dark areas in the same scene. Another example of hard light is when the camera's flash is the only light source, resulting in bright subjects against a very dark background. Use the dark shadows as design elements or soften them with fill flash if you're within range.
Soft light
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Soft light is very camera-friendly—smooth, diffuse, even, with few shadows to confuse your camera. Cloudy days and large shaded areas offer soft light with no harsh shadows or intense bright spots.
Light even has colours. Early or late in the day, sunlight has a warm golden glow. Frigid temperatures in a snow-covered landscape can be conveyed with bluish noon-hour light.
Light even has colours. Early or late in the day, sunlight has a warm golden glow. Frigid temperatures in a snow-covered landscape can be conveyed with bluish noon-hour light.
Fluorescent
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Fluorescent lamp or fluorescent tube is a gas-discharge lamp that uses electricity to excite mercury vapor. The excited mercury atoms produce short-wave ultraviolet light that then causes a phosphor to fluoresce, creating visible light. A fluorescent lamp converts electrical power into useful light more efficiently than an incandescent lamp. Lower energy cost typically offsets the higher initial cost of the lamp. The lamp fixture is more costly because it requires a ballast to regulate the current through the lamp.
While larger fluorescent lamps have been mostly used in commercial or institutional buildings, the compact fluorescent lamp is now available in the same popular sizes as incandescent and is used as an energy-saving alternative in homes.
The United States Environmental Protection Agency classifies fluorescent lamps as hazardous waste, and recommends that they be segregated from general waste for recycling or safe disposal.
Physical discoveries
Fluorescence of certain rocks and other substances had been observed for hundreds of years before its nature was understood. By the middle of the 19th century, experimenters had observed a radiant glow emanating from partially evacuated glass vessels through which an electric current passed. One of the first to explain it was the Irish scientist Sir George Stokes from the University of Cambridge, who named the phenomenon "fluorescence" after fluorite, a mineral many of whose samples fluoresce strongly due to impurities. The explanation relied on the nature of electricity and light phenomena as developed by the British scientists Michael Faraday and James Clerk Maxwell in the 1840s.
While larger fluorescent lamps have been mostly used in commercial or institutional buildings, the compact fluorescent lamp is now available in the same popular sizes as incandescent and is used as an energy-saving alternative in homes.
The United States Environmental Protection Agency classifies fluorescent lamps as hazardous waste, and recommends that they be segregated from general waste for recycling or safe disposal.
Physical discoveries
Fluorescence of certain rocks and other substances had been observed for hundreds of years before its nature was understood. By the middle of the 19th century, experimenters had observed a radiant glow emanating from partially evacuated glass vessels through which an electric current passed. One of the first to explain it was the Irish scientist Sir George Stokes from the University of Cambridge, who named the phenomenon "fluorescence" after fluorite, a mineral many of whose samples fluoresce strongly due to impurities. The explanation relied on the nature of electricity and light phenomena as developed by the British scientists Michael Faraday and James Clerk Maxwell in the 1840s.
Quality of Light
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Light is said to have different moods based on setting for example out in the open, on a sunny day at noon, you’ll be faced with hard, defined shadows. The quality of light affects the mood of the picture.
Colour Balance
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Sometimes the adjustment to keep neutrals neutral is called white balance, and the phrase color balance refers to the adjustment that in addition makes other colors in a displayed image appear to have the same general appearance as the colors in an original scene.
In photography and image processing, color balance is the total change of the strengths of the colors within a photograph which is usually primary colors. This is mostly taken in to concern to reduce specific colors – particularly neutral colors. The most known methods are sometimes called, neutral balance, gray balance or white balance. Color balance changes the overall mixture of colors in an image and is used for color correction; generalized versions of color balance are used to get colors other than neutrals to also appear visually as good as possible which is where HD is developed from.
The color balance process in popular image editing applications usually operate directly on the red, green, and blue channel pixel standards, without respect to any color sensing or reproduction model. In shooting film, color balance is typically achieved by using color correction filters over the lights or on the camera lens.
Image statistics developed by sensors, either electronic image or film sensors must be transformed from the developed standards to new standards so that its changed to the best type of format to be displayed. Several parts of the achievement and display process make such color correction essential including the fact that the achievement sensors are very different to how an individual would view it.
In photography and image processing, color balance is the total change of the strengths of the colors within a photograph which is usually primary colors. This is mostly taken in to concern to reduce specific colors – particularly neutral colors. The most known methods are sometimes called, neutral balance, gray balance or white balance. Color balance changes the overall mixture of colors in an image and is used for color correction; generalized versions of color balance are used to get colors other than neutrals to also appear visually as good as possible which is where HD is developed from.
The color balance process in popular image editing applications usually operate directly on the red, green, and blue channel pixel standards, without respect to any color sensing or reproduction model. In shooting film, color balance is typically achieved by using color correction filters over the lights or on the camera lens.
Image statistics developed by sensors, either electronic image or film sensors must be transformed from the developed standards to new standards so that its changed to the best type of format to be displayed. Several parts of the achievement and display process make such color correction essential including the fact that the achievement sensors are very different to how an individual would view it.
Tungsten lighting
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Tungsten is a solid, rare metal under standard conditions when uncombined, tungsten is found naturally on Earth only in chemical compounds. It was identified as a new element in 1781, and first isolated as a metal in 1783.
Tungsten light is a type of incandescent lighting using a bulb with a filament made of the metal tungsten. Unless you have switched to compact fluorescents, most of the lighting in your home is tungsten. In still shooting, tungsten lighting is said to give studio photographers greater flexibility than the classic ‘north sky light’. Tungsten lights have been most popular for many years in commercial studios until the introduction of strobes (or speed lights) and some workers still prefer tungsten for its ‘controllability’. For television and cinematography tungsten is vital.
Tungsten lighting, a form of hot or continuous lighting in studio applications, finds its most prevalent use in video applications. Some digital still photographers and portrait photographers prefer tungsten lighting for its consistency. Tungsten lights create dramatic possibilities in wedding photography, particularly since an assistant can move the light around until the photographer gets the highlight he wants. On the other hand Tungsten lights generate a lot of heat in combination with the light. This heat involves photographers to use great care and time with tungsten lights. Reflectors, umbrellas, and soft boxes, which all modify the light, must be designed specifically to withstand the severe temperatures created by tungsten lighting.
Tungsten light is a type of incandescent lighting using a bulb with a filament made of the metal tungsten. Unless you have switched to compact fluorescents, most of the lighting in your home is tungsten. In still shooting, tungsten lighting is said to give studio photographers greater flexibility than the classic ‘north sky light’. Tungsten lights have been most popular for many years in commercial studios until the introduction of strobes (or speed lights) and some workers still prefer tungsten for its ‘controllability’. For television and cinematography tungsten is vital.
Tungsten lighting, a form of hot or continuous lighting in studio applications, finds its most prevalent use in video applications. Some digital still photographers and portrait photographers prefer tungsten lighting for its consistency. Tungsten lights create dramatic possibilities in wedding photography, particularly since an assistant can move the light around until the photographer gets the highlight he wants. On the other hand Tungsten lights generate a lot of heat in combination with the light. This heat involves photographers to use great care and time with tungsten lights. Reflectors, umbrellas, and soft boxes, which all modify the light, must be designed specifically to withstand the severe temperatures created by tungsten lighting.