The UV filter is an ultraviolet filter. Its main purpose is to protect optical lenses from damage, dust and dirt (all this quickly destroys the lens). Also such optical elements detain ultraviolet radiation when shooting distant objects. After all, the digital matrix and photographic film, in contrast to the human eye, are more sensitive to this type of radiation. UV-filter is very useful for shooting in mountainous terrain, it helps to avoid the blue coating on the photos.
The entire region of the ultraviolet spectrum can bedivided into 3 ranges: long-range - 280 nm and shorter (UV-C); the average is 320-280 nm (UV-B); and the nearest one is 400-320 nm (UV-A). The sensitivity of digital technology is lower than the film sensitivity, so it takes the near range, and the film is able to fix the entire region of the ultraviolet range (but the human eye can not see in one of these ranges). However, the capabilities of film cameras limit the possibility of optical lenses. The UV filter cuts this radiation at 320 nm (medium and long range).
When choosing such a product, you needrepel the diameter of the lens. That is, to find out which filter is suitable for your camera, you need to know the diameter of the thread of the lens (it is indicated on the lid on the inside). The price of the product depends on its size. So a UV-filter with a diameter of 52 mm costs 10-15 dollars, and 77 mm - 30-40 dollars.
It is accepted to divide filters of category UV into four groups:
Despite the external differences, the goal of this group is one - protection of the lens from external influences, ultraviolet and haze. The most popular are the UV-filter and Skylight.
Very often sellers present Skylight asthe best and, accordingly, expensive, but the effect of warm tones on the photo is intended only for film cameras, on the figure it is reduced to zero by the presence of a white balance.
Use UV filters or not, it should be solveditself amateur photographer, but take measures to protect the lens is necessary, because the price of a good optical system can be even higher than the cost of the camera itself.
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