Understanding of the camera image
On 12 Oct 2011
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The camera with the formation of image is simultaneously, and BaiGuangZe is composed of different wavelengths of visible light combination and into. Although with electromagnetic wave, but is different wavelengths of visible light (color) in through the glass will there be different speed, so also have so-called different refractive index. This principle is used, we want to use the mirror will be white light OS will be decomposed into different colors (wavelength of light). By glass a camera, the use of refraction principle will be focused upon and visible image. The light through the lens, have the opportunity to appear similar rhombohedrons result of mirror, different wavelength of light in the same focus not on the image formation in focus, dispersion, which is called the purple edge is like. We can understand the color difference through the lens in the central and edge image how to form the dispersion is like. In theory in the central and edge image dispersion can happen, but due to the edge of the light a long process, so the dispersion is particularly evident. Because of short wave long high index of purple color difference, so also particularly sensitive. Formed by the color difference of purple edge, usually you can see in the picture, and with the purple edge refraction, so more purple edge are generally spread from inside to outside. In addition, the light of the telephoto lens, the dispersion process long now like more easy to see. Now in the edge like dispersion lens is obvious, and purple edge are generally spread from inside to outside. The image of the purple edge less central dispersion. To solve the problem, and the camera manufacturers have off color from the structure of the lens trying to, including using different of refraction, scattering characteristics of lens combination. Canon early success to artificially fluorite crystal (CaF2) low dispersion characteristics of greatly reduced lens off color, released in 1969 and the first team fluorite elements symbolism of the lens FL-taken F300mm f / 5.6. Today, fluorite elements and UD ultra-low dispersion lenses already is widely used in the Canon EF lens in high quality. Two pieces of UD lens equivalent to a piece of fluorite elements of the blue poor effect, and a super UD lens can be equivalent to a provide fluorite elements of efficacy. uk online:http://www.batterieschargerstore.co.uk Go to Category Digital Cameras | Previous Page |
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