Traditional Culture Encyclopedia - Photography major - Application of HOYA HD circular polarizer in removing stray light and purifying images

Application of HOYA HD circular polarizer in removing stray light and purifying images

In the film age, IT 168 evaluation center often uses various filters to take photos. Special effects? But in the digital age, many filters have been replaced by software. However, for digital cameras, there are also some filter effects that cannot be easily achieved by software, such as polarizers.

Hoya HD CIR PL

Because light is also an electromagnetic wave, the wave surface is directional, so light can be? Grating? Filter. Circular polarizer (CPL) can be simply explained as? Grating? It allows the light whose wave front direction is parallel to the grid to pass through, while other light rays will be weakened or even eliminated.

Polarization (reflection) and analysis of light (circular polarizer)

In nature, the wave front of the light emitted by the light source is often mixed in all directions, that is, the light will be weakened after being filtered by the circular polarizer, but it will not be eliminated. However, the light reflected by non-metallic surfaces is often polarized light in a single wave direction, which can be eliminated by circular polarizer. As shown in the above figure, the wave front of the light emitted by the light source is uncertain, but after being reflected by some nonmetallic surfaces, there is only a wave front in a specific direction. This process is equivalent to that shown in the above picture? Deviation? ; When we shoot this reflected light through a circular polarizer, the reflected light may be weakened or even eliminated according to the angle of the polarizer. This process can be understood as? Deviation detection? . When a circular polarizer is used in photography, this principle is used to remove some light and keep others.

Hoya HD CIR PL

Hoya HD CIR-PL is a new type of circular polarizer introduced by Hoya. Hd? It not only represents high-density glass, but also implies multi-layer coating, thin frame, high-pressure assembly and excellent antifouling and waterproof performance.

Selection and use of circular polarizer

The circular polarizer is installed on the lens, and the filtering effect can be observed through the TTL viewfinder (SLR camera) or display screen (compact digital camera) of the camera. By rotating the circular polarizer to different angles on the lens, you can get different filtering effects, and you will find that the whole picture may be darkened or some reflections will be eliminated.

Use of circular polarizer

The above picture shows Hoya HD CIR-PL installed on Canon EF 50mm 1: 1.8 lens. Then, when we buy a polarizer, how can we judge or identify the quality of the polarizer? Actually, there is a very simple method.

Generally, the display images of LCD (such as camera) are polarized light, so circular polarizer has a good filtering effect. Shall we put a circular polarizer on the LCD screen? Attention, make sure that the side of the threaded bayonet on the polarizer faces our observer? When the polarizer rotates to a certain angle, the picture you see should be the brightest. The closer this picture is to the observation effect without filter, the smaller the optical loss of polarizer in the specified direction. Of course, the smaller the abnormal color, the better the polarizer.

Polarized light transmission effect of Hoya HD CIR-PL

Turn the filter again until the image viewed through it is the darkest. At this time, most of the light transmitted from the display screen should be filtered out. So the darker the picture you see, or even completely black, it means that the polarizer has better filtering performance for the specified light.

Polarization blocking effect of Hoya HD CIR-PL

Judging from this simple test effect, HOYA HD CIR-PL is good enough in terms of light transmission and shielding. And how does it behave in the shooting? Let's take a look at the actual shooting effect.

Application of circular polarizer and HOYA HD CIR-PL sample

1. Shoot still life in natural environment such as flowers to improve the light ratio and color of the picture. The leaves in the picture below reflect strongly in the sun, and we have improved the picture effect through the use of polarizers.

Filerless shooting

Using Hoya HD CIR PL does not change exposure shooting.

Use Hoya HD CIR-PL and increase exposure shooting.

The contrast effect of the above three photos.

Because of local reflection, the light ratio of the picture taken without filter is very large, and most of the green color becomes dark. After adding HOYA HD CIR-PL and adjusting the angle, the highlights are almost eliminated, but the whole picture is very dark. Therefore, in the third photo, we increased the exposure, thus obtaining a more balanced tone and bright color.

2. Used to darken the sky when shooting scenery. After some polarized light in the blue sky is filtered, the sky will be more pure. Using polarizers can emphasize the hue of the sky, and if there are white clouds in the sky, it will also enhance the contrast between the blue sky and white clouds.

Filerless shooting

Shooting and Hoya HD CIR-PL

3. Eliminate local reflection when shooting products. When shooting reflective products, it is difficult to avoid some reflections and reflections. At this time, these messy lights can be reduced by using polarizers. Of course, the effect of filtering plane reflection is better than that of curved surface reflection. Pay attention to the reflection on the hood and windshield of the car and the red frame on the speaker in the following example.

Filerless shooting

Shooting and Hoya HD CIR-PL

Filerless shooting

Shooting and Hoya HD CIR-PL

4. Shoot glass display cases or underwater objects. In fact, photographing objects in glass windows is one of the most common uses of circular polarizers. Water surface and glass have the same effect. They will reflect some strong light, so that you can't shoot the objects inside through the surface normally. Then you can get a good transmission effect by using a polarizer. For example, the following example.

Filerless shooting

Shooting and Hoya HD CIR-PL

IT 168 Evaluation Center's point of view: From the product technology and antifouling and waterproof performance, HD series, as a high-end filter series of HOYA, has good basic performance. From the transmission and elimination effect of the specified light, HOYA HD CIR-PL also performed well, and the filtering effect was obvious. But in some cases, especially under artificial light, HOYA HD CIR-PL will have an impact on the overall tone of the picture. Compared with B+W and Ken brands on the market, HOYA HD CIR-PL has moderate price and good cost performance.