What is a PL filter?

PL filters generally refer to polarizers, which are also called polarizers and are divided into two types: circular polarization (CPL) and linear polarization (PL). The polarizer is an accessory accessory of the camera and is installed on the front of the lens. .

It is a kind of adhesive film with two layers of glass bonded together, with a very fine rod-shaped crystal sandwiched in the middle. This adhesive film can polarize light, so it is called a polarizing film. . When the light with transverse vibration passes through the polarizer, it becomes a one-way vibration, and the vibration in other directions is partially or completely absorbed. Therefore, the light wave after passing through the polarizer only vibrates in a plane parallel to the crystal filament in the mirror.

When shooting with a polarizer, the polarizer should be placed in front of the photographic lens, and the mirror should be rotated while observing through the viewfinder to observe the effect of eliminating polarized light. When you observe that the reflection of the object disappears, you can stop rotating the mirror.

What are the uses of polarizers in photography?

Polarizers have the following uses in photography: controlling the brightness of the sky and making the blue sky bluer. The polarizer has the function of blocking the bright light in the sky. When the direction of the polarizer is 90° to the sunlight, the bright light in the sky is blocked; when the direction of the polarizer is 0° or 180°, it has no polarization effect. Since there is a lot of polarized light in the blue sky, a polarizer can be used to adjust the brightness of the sky. After adding a polarizer, the blue sky becomes very dark, highlighting the white clouds in the blue sky.

Flare or reflection often occurs on water surfaces, display cabinets, painted surfaces, plastic surfaces, etc., which is caused by the polarization of light. Using a polarizing filter when shooting and rotating the polarizing mirror appropriately can block these polarized lights, thereby eliminating or weakening the reflections or bright spots on the surface of these smooth objects, and better showing the details and texture of the subject. During use, if the angle between the two polarization axes can be rotated, different degrees of light blocking can be obtained.

Polarizers are gray, so they can be used in both black and white and color photography. Can be used as a neutral gray filter. Since the polarizer is gray, if two polarizers are superimposed, it can prevent part of the light from passing through and act as a neutral gray filter. Eliminate or weaken the reflected light on the surface of smooth objects. When shooting objects with smooth surfaces, such as glassware, improve the color purity of color images. Using a polarizer can eliminate reflections and flares on smooth objects. The reflection or flare of the object not only makes this part of the image lose its texture, but also significantly reduces the color purity of the subject's color, eliminates the reflection and flare on the subject's surface, and at the same time improves the color quality to varying degrees. The color purity of the image.

What should you pay attention to when using polarizers?

1. After using a polarizer, the amount of exposure should be appropriately increased. Because the polarizer has a certain light-blocking effect, and the thin and strong crystalline filaments in the polarizing film are made in different ways, their transparency is also different, so the exposure factor is also different. Generally speaking, the increase factor is about is 2-4 times.

2. Be careful not to let light shine directly on the lens to avoid halo phenomenon. It is best to use a lens hood.

3. When using, the mirror should be rotated continuously to obtain the best effect.

4. When photographing objects or taking pictures under artificial light, you can add a polarizing plate in front of the light source or a polarizing filter on the lens, but the polarizing plate cannot be used on the photographic lens, and the polarizing filter cannot be used on the photographic lens. It cannot be used in front of a light source. Because the two have different shapes and sizes, and their performance is also slightly different, they cannot be mixed.