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[Concept]
(Skylight filter) referred to as SL mirror can absorb ultraviolet light, but UV mirror can effectively absorb ultraviolet light, but the role is not the color balance the Skylight in addition to the outside with UV mirror function, but also play the role of color balance.
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Classification
Generally divided into: 1A / 1B
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[1A]
1A pale orange-red, and it can be used to weaken a small amount of blue and ultraviolet light.
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[1B]
1B pale magenta.
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Bluish hue of the phenomenon of two Skylight in addition to having a UV mirror function, respectively at 500nm green (1A), 550nm yellow green (1B) to absorb an amount of approximately 10%, in order to reduce the scattering of light caused sky scene flash photography can correct the bias light blue, 1A corrective blue slightly stronger than 1B.
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[Role]
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1 [to adjust the color temperature]
Get excellent color reproduction and high purity of the screen to take a color photo in the clear sunlight.
Especially when shooting sunny outdoor portraits, to prevent reflective figure next to objects, maintain the natural real people's skin.
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2. [Without compensation amount of exposure]
Skylight does not require compensation amount of exposure, it is often installed in front of the camera used to protect the camera lens to make it free from dust pollution and a variety of possible rub, bumps.
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3 [instead of UV lenses] for protection mirror
In most cases, the Skylight can replace the UV lenses as a protection mirror remains in the lens, of course, it is, after all, belongs to correct the color temperature of the filter will was warm, to some extent, affect color reproduction.
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The lens protection with special protection mirror is best, followed by the the UV mirror again Skylight.
Because it will change the color temperature, UV mirror and Skylight used to protect the lens are only part-time, if no special requirements, the proposed election of UV mirror, it is relatively cheap in the filters of the same file.
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[Effect]
Effect for black and white film, Skylight and less obvious.
For a color film, especially in the case of pale blue light, such as cloudy or more foggy weather, the effect is very obvious.
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[Disadvantage]
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1 [reduce clarity]
The use of any filter is equal to the increase in the subject to the film of the clear light path with a layer of barrier. Therefore, even if only slightly affected, but still reduces the sharpness of the image.
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2. Increase the possibility of glare]
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Therefore, if you want the photo to obtain the greatest possible clarity, unless there is sufficient reason, it is recommended that as much as possible not to use any filter.
Protect the lens is not a good reason, unless we're going to sandstorms or splashed beach or indeed have lens damage the environment.
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【Article is excerpted from: Baidu Encyclopedia】
【Network reprint / Just reference】
【Translation is by Goolge】
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