Canon 5d2 lens 24- 105, what kind of polarizer should I buy? I mainly want to shoot better white clouds and blue sky, please introduce it in detail, thank you!

1, clear sky Wan Li, wants to make the blue sky bluer.

2, clear blue sky, blue sky has dyed all the scenery with a layer of blue. I want to eliminate the blue in the scene and make it more saturated.

3. I 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.

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.

The function of PL mirror is to filter the reflected light and increase the imaging contrast. Its working principle is to selectively filter light from a certain direction. By filtering out a lot of polarized light in diffuse reflection, the light intensity in the sky is weakened, the sky is darkened and the contrast between the blue sky and white clouds is increased. Look at the viewfinder and rotate the front mirror when shooting. In the viewfinder, the effect is most obvious when the sky is darkest, and the difference between the darkest and the most appearance is 90 degrees. You can turn to any angle between the darkest and brightest as needed.

PL mirror can also effectively weaken or eliminate the reflection of nonmetallic surface, which is a typical polarized light (the light reflected by metal surface is not polarized light, and the polarizer has no effect on it). By adjusting the polarizer, this part of the reflection can be filtered out, thus improving the imaging quality of the subject and the clarity of the picture. For example, using a polarizer can reduce the reflection of the water surface, so that you can clearly photograph the fish in the water. When shooting such a scene, the projection angle of the light source should be close to the projection angle of the camera, and the maximum deflection angle should be between 30 and 40 degrees. When in use, it can be adjusted by slowly rotating the lens in front of the filter to minimize the reflection on the scene surface.

In addition, the polarizer can effectively improve the color saturation and contrast, because it can absorb the stray light reflected by fog or dust in all directions in the atmosphere, thus making the photographed image more pure. For example, in the still life photography of flowers, a polarizer is often used to take color photos. In landscape photography, flower photography and shooting some specific polarizers.

Very useful when the reflection is strong. When the polarizer is used to take landscape photos, it has an excellent effect on depicting clouds. The refractive index of light in the blue sky is greater than that of light scattered by white clouds. Using polarizer can also make the color of green leaves more saturated and eliminate the fog of shooting urban scenery at low angles.

-from the encyclopedia

Then my answer: the polarizer can adjust the blue to the right or left, and the polarizer can rotate to adjust the depth and depth of field of the blue, and so on. You have to go through some skills when you rotate, such as the brightest time, the bluest time and so on. You can do this by rotating the polarizer.