<script>on mouseUpput the short name of this card into xTempput char 2 to 6 of xTemp & ".mov" into Movie--put Movieif Movie is not empty then-- put "Animations:" & Movie into pMovieplayMovie Movie,"Animations:"end ifend mouseUp</script>
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<id>25</id>
<text><span class="style10">hotography and Film (3 of 4)</span><span class="style7"></span><span class="style10">Modern cameras</span><span class="style7">Unlike more traditional 35 mm cameras, which have a simple see-through view-finder, the 35 mm single-lens reflex camera allows the user to see the exact picture being taken. Larger cameras may also use the reflex viewfinder. In the case of the twin-lens reflex, the mirror is fixed and has its own lens, of the same characteristics as the taking lens. Although the 35 mm film size is the most popular, larger formats, using sheet film or roll film, are still used where convenience of use is less important than final picture quality.More sophisticated 35 mm cameras have their own </span><span class="style19">exposure meters</span><span class="style7">, which measure the amount of light falling on the subject and adjust the shutter speed and lens aperture accordingly. They may also incorporate electronic controls and automatic focusing: the user is required only to frame the picture and press the trigger.</span><span class="style10">Film and color photography</span><span class="style7">Emulsions have improved continuously. An early step was the introduction of </span><span class="style19">panchromatic</span><span class="style7"> film, which was sensitive to red and therefore gave a better tonal rendering. Subsequent films of still greater sensitivity enabled pictures to be taken in poor light, but tended to be less sharp because the silver grains were larger - although this problem was itself solved by the later introduction of sensitive fine-grain films.Cumbersome ways of making color pictures were evolved in the late 19th century, but it was the appearance of Kodachrome and Agfacolor in the 1930s that introduced modern color films. These were multi-layer films in which three separate emulsions recorded the blue, green and red parts of the image. They were then processed by dyeing each layer with the corresponding complementary color (yellow, magenta and cyan), thus producing three positive images one above the other, which together reproduced the original colors of the image. The final picture was a transparency, to be looked through or projected, but a negative/positive system was soon introduced to produce color prints.</span></text>
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<id>26</id>
<text><span class="style10">n a single-lens reflex (SLR) camera</span><span class="style7">, a single lens is used both for viewing and for taking the picture. A hinged mirror set at 45 degrees directs the image projected through the lens onto a ground-glass focusing screen above the mirror. The laterally reversed image on the screen is then reflected off the sides of a pentaprism (five-sided prism), so that the image is then focused on the screen, and the iris diaphragm is set to contract automatically to the correct aperture as the picture is taken. As the shutter-release button is pressed, the mirror swings up and the shutter opens, thus allowing the image to strike the film.Focal-plane shutter, located between mirror and film. As the shutter is released, the first blind, normally covering the film, moves across to expose the film. The second blind follows rapidly behind, to cover the film again.Iris diaphragm, adjusted to control the amount of light admitted through the lens. The diaphragm consists of a set of overlapping hinged blades that move in such a way as to increase the opening, or aperture, at the center of the diaphragm.</span></text>
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<text>ΓÇó OPTICSΓÇó RADIO, TELEVISION AND VIDEOΓÇó SEEING THE INVISIBLEΓÇó PHOTOGRAPHY AS ARTΓÇó CINEMA</text>
