Type of filter

Filter type: black and white filter 1. Full color filter This filter is used to adjust the brightness level of the image to adapt to the sensitivity of the naked eye and make the picture produce natural brightness. Commonly used filters are Y48 yellow mirror and YG yellow-green filter. 2. Emphasize the filter This filter is to mix short-wavelength light (purple and blue). Eliminating the strong contrast between light and dark that darkens the blue sky or blue sea can emphasize the color tone of the picture. There are two kinds of filters: orange filter (O56) and red filter (R60). Color filter 1. Color temperature conversion filter (LB). There are two kinds of mirrors, that is, the color light is blue when it is cloudy or rainy. Using LB-A4 color mirror for correction can make the color look natural. But taking pictures under the light, the color is red. LB-B 12 color mirror can be used to correct color temperature. Filter subtracter is also called neutral density mirror. Because the color of the lens is gray neutral color, this filter can not only reduce the amount of light passing through, but also have the function of not changing color. Therefore, whether it is used for color photography or black and white photography, there will be no deviation in wavelength and color temperature. Subtractors can be divided into several types according to density, such as ND2 ND4 ND8 and so on. The larger the value indicated in the filter, the higher the density and the stronger the dimming ability. The transmittance of ND2 is 1/2 (the first aperture needs to be opened for exposure), that of ND4 is 1/4 (the second aperture needs to be opened for exposure) and that of ND8 is 1/8 (the third aperture needs to be opened for exposure). The purpose of the reducing mirror: A. Reducing the sensitivity of the film A reducing mirror can reduce the amount of light passing through the lens and reduce the sensitivity of the film. B. it shows the blurring effect of short depth of field. After the reducing mirror is covered on the lens, it is necessary to increase the aperture to get enough light, so as to blur the front background. C. show the effect of slow shutter. Even if the aperture is narrowed under strong light, the shutter speed cannot be reduced to a suitable slow speed. Using a higher power ND mirror can reduce the shutter speed and make the dynamic subject have a dynamic effect. D. Only by applying the ultra-high density ND400 subtracter can the long exposure effect be shown in bright daytime, which can reduce the shutter speed by nine levels. 3. Polarizing filter. R) Polarizing filter, also known as polarizing filter, is a special filter, which can be applied to black-and-white and color photography. It can eliminate the reflection on the surface of the object, and make the photographed scenery image clearer and richer in color. It is a necessary lens besides UV filter. Polarizers can be divided into two types-linear polarization filters. And a circularly polarized filter for manual focusing or automatic focusing, respectively, and a linearly polarized filter. : It can only be used in manual focus cameras. When it is used in an autofocus camera, it will cause errors in the light measurement of the camera. Circular polarization filter, which can be used for automatic focusing and manual focusing cameras. The price is more expensive than linear polarizer. Usage of polarizer: The structure of polarizer is usually composed of two transparent optical glasses with a plastic polarizing film sandwiched between them. When we rotate the front mirror of the polarizer, if the polarization direction of the reflection on the surface of the object is at right angles to the polarization film of the filter, the reflection on the object will be weakened because of polarization. (Dimming) At other angles, the polarizer will allow some or all polarized light to enter. Therefore, the observer can directly see the use effect of the polarizer by observing the rotation of the polarizer sleeved on the lens of the SLR camera. The place where the reflective part turns from bright to dark is the best angle to eliminate reflective light. Polarizer is a neutral gray lens, which has no influence of color cast, so it can be used for color or black-and-white photography. In addition, the polarizer will also reduce the passing light by about four times (that is, two-stage exposure), so it can also replace the ND filter. Use. Use and function of polarizer: a. Eliminate unnecessary reflection. Glare produced by all nonmetallic reflecting surfaces can be eliminated by polarizers. However, the degree of elimination depends on the angle of reflected light and polarizer. As for the mercury in the reflection of metals and lenses or electroplated products, it is impossible to eliminate it. B. emphasize light and color. Eliminating polarization can not only increase the clarity and color saturation of the image, but also make the color of the scene more vivid. C. the polarizer itself has the function of absorbing ultraviolet rays. Blue mist, which is used to shoot scenery, can narrow the foreground and make it clearer and brighter. 4. skylight filter -SL filter. Vertical lens for color photography. Pale pink can eliminate ultraviolet rays. It can also be used as a protective filter for color photography. 5. UV filter-UV filter. Used to eliminate ultraviolet rays, can improve the clarity of the image. Lenses are colorless and transparent, and can often be used as protective lenses. 6. Soft light is irregular. There are tiny bubbles on the lens, which disperse the penetrating light and produce soft light focus. Advanced filters will replace tiny bubbles with tiny silver particles. There are usually two grades of softness. Some will be divided into five levels. The higher the level, the stronger the softness. Take Nikon as an example, Soft65438. Softer 2. Softer 2 has stronger softening effect than Softer 1. When the light is distributed around the subject, the effect produced by using this lens is particularly good. The sharp contrast between the subject's Ming Rui and its surroundings creates an illusion. When used in portrait landscape or still life photography, it can add a soft atmosphere. When using this filter, you should pay attention to using a large aperture. Or a focal length lens above a medium distance. If you use a fine aperture or a wide-angle lens for soft focusing, the effect is not obvious. Price reference: search.stores.ebay/. Alpine Topline _ Filter _ W0QQQCIZQ2D1QQQCLZ3QQQSzAlpinePlineQSooz1QQQSOPz2QQQSelz1 94307285 qgsofpz 0 Reference: wahyan.edu/. ylchan/photo-course/filter Linear and circular polarizers are used respectively, and can only be placed on the lens where the helicopter front lens does not rotate with the focus ring.