What is a polarizer, how to use it when shooting, and what is the market price of a general polarizer?

Polarizer, also called polarizer, referred to as PL mirror, is a kind of color filter. The excellent function of polarizer is that it can selectively let the light that vibrates in a certain direction pass through, and it is often used to eliminate or weaken the strong reflection of non-metallic surface in color and black-and-white photography, thus eliminating or reducing the light spot. For example, in landscape and scenery photography, it is often used to show the texture of objects with strong reflection, highlight the scenery behind the glass, darken the sky and show blue sky and white clouds. It consists of two pieces of optical glass sandwiched by a tiny polarizing crystal (such as mica) with directional function. There is also a manufacturing method. The interlayer between two pieces of optical glass is coated with crystals, such as polyethylene film or poly (vinyl cyanide). This polymer coating can produce a very fine fence-like structure, allowing only light in the same direction as the vibration of the gap to pass through. Then two pieces of glass are independently installed in a rotatable ring, and the polarized reflected light on the surface of the object can be eliminated by rotating one of the lenses. The coating will be circularly polarized (CPL)

Gradually aging failure, and moisture, impact and vibration will shorten the service life. After all, PL coated with polymer is consumable, not durable. Under normal circumstances, it is no problem to use it for five or six years.

Where the polarizer is used: Comparison of photos before and after using the polarizer.

1, clear sky Wan Li, wants to make the blue sky bluer. 2, clear blue sky, blue sky dyed all the scenery with a layer of blue. I want to eliminate the blue in the scene and make it more saturated. 3. When shooting an object in the water, the water surface reflects light and the object cannot be seen clearly. Want to shoot objects in clear water, such as swimming fish; Or trying to make the water deeper. 4, shooting still life, want to eliminate the reflection on the surface of the object. I want to shoot something behind through the glass.