Classification of camera filters

Lens filters are also called color filters, or filters for short. Using filters is an important part of photography. Filters have two meanings: First, traditional filters. A lens or lens group installed in the optical path to adjust and control the nature (color, intensity, polarization) and propagation direction (refraction, diffusion, diffraction) of light to change the image tone, tone, shape, and clarity. The filter is a light-transmitting medium, and the best quality filter also has side effects, which will reduce the clarity and sharpness of the image to varying degrees. Therefore, unless it is necessary, in general, try not to use it. For example, when there is polarized light in the sky or when you want to make the blue sky bluer, you need to use a polarizer. On a sunny day, you need a UV lens for plateau ultraviolet rays. If the sun is not red at sunrise and sunset, an orange filter can be used to create a twilight atmosphere. The most commonly used are UV mirrors, polarizers, mid-gray filters, mid-gray gradient filters, color temperature conversion filters and color temperature compensation filters. Second, digital filters. Digital filters can be subdivided into in-camera filters, that is, the white balance function of digital cameras. Post filter. Also known as computer filter, a computer software function used to process image special effects.

What are the classifications of filters?

According to the purpose: there are photographic filters (installed in front of and behind the photographic lens, black and white photographic filters, color photographic filters and black and white color universal filters), lighting filters (installed in front of photographic lamps) And printing filter (installed in the enlarging machine, enlarging machine). Generally speaking, the filter refers to the photographic filter.

According to whether it is selective. Selective filters (only pass through the same or similar colored light or cut off certain kinds of light, such as skylight, UV, and various color filters) and non-selective filters (all colors can pass through , But the illuminance is reduced, such as in the gray mirror).

According to special effects. There are diffuse mirrors (diffuse mirrors, fog mirrors, contrast mirrors, etc.), halo mirrors, gradient mirrors, half-color mirrors, polarizers, close-up mirrors, starlight mirrors, multi-image mirrors, deformable mirrors, dynamic mirrors, and mirrors , Rainbow Mirror, etc.

Classified by hue. There are warm tone filters (color amber, logo W or A, R), cold tone filters (color light blue, logo C or B).

According to color temperature. There are color temperature conversion filters and color temperature compensation filters. Mainly used for film cameras. Because digital cameras have a white balance function for color temperature, color temperature conversion filters and color temperature compensation filters can be eliminated.

Classified by material. There are optical glass filters and plexiglass filters.

According to the installation method. There are spiral coupling filters and socket coupling filters. The complexity of light used in photography determines the variety of filters, which is reasonable.