Photographic terminology

The front boundary of the depth of field and the back boundary of the depth of field respectively * * * the distance between the two imaging planes of the yoke. Image depth corresponds to the depth of field, and the greater the image depth, the greater the depth of field.

The standard for determining the depth of field: 135 The diameter of the blur circle allowed by the camera is generally 1/30 mm, that is, 0.033mm..

Hyperfocal distance:

When the lens is focused at infinity, the scene at infinity forms a clear image, and at the same time, the object at a certain point at a limited distance can reach a clear standard, and the object near this point is blurred, so the distance between this object and the lens is hyperfocal distance.

Focal length:

The distance from the center of the lens to the focus. The unit of focal length is usually expressed in mm (millimeter). The focal length of the lens is usually marked in front of the lens, for example, f=50mm (this is what we usually call a "standard lens" because its viewing angle is the same as that of the human eye), and the focal length of 28-70mm (our most commonly used lens) is most suitable for taking portraits, 70-210 mm.

Aperture:

A device that controls the amount of light passing through a lens. The aperture is represented by f, including f 1.0, f 1.4, f2.0, f2.8, f4.0, f5.6, f8.0, f1,f 16 and f22.

Shutter (shutter)

Device for controlling exposure time. Shutters can generally be divided into curtain shutters, lens shutters and steel shutters. Among them, curtain blinds can be divided into vertical curtain blinds and horizontal curtain blinds. Steel shutter can reach higher speed (the highest shutter speed can reach112000 seconds or more at present). Generally, the highest speed of the inter-mirror blade shutter does not exceed 1/500 seconds, but the biggest advantage of the inter-mirror blade shutter is that the noise generated during shooting is extremely low, which is very conducive to sneak shots and can realize synchronous flashing within the full speed range.

Shutter speed (shutter speed)

Opening time of shutter. It refers to the time (exposure time) when light sweeps across the film. For example, "1/30" means that the exposure time is 1/30 seconds. Similarly, "1/60" means that the exposure time is1/60s, and the shutter of1/60s is1/30s. The rest and so on.

Note: Some materials refer to shutter speed as shutter time. The two names are different, but they mean the same thing, both referring to the shutter opening time.

depth of field

The relatively clear range of the image. The depth of field depends on three factors: the focal length of the lens, the distance between the camera and the subject, and the aperture used. The relationship between depth of field and the above three factors is: the longer the focal length, the shorter the depth of field; The shorter the focal length, the longer the depth of field (for example, under the same aperture and distance, the scene of 28mm lens is far greater than that of 70mm lens); (2) The closer the distance is, the shorter the depth of field is, and the farther the distance is, the longer the depth of field is (for example, under the same focal length and aperture, the subject scene at 10 m is far greater than the subject depth of field at 1 m); (3) The larger the aperture, the shorter the depth of field, and the smaller the aperture, the longer the depth of field (for example, under the same focal length and distance, the scene with the aperture of F 16 is far greater than the depth of field with the aperture of F4).

Depth of field preview:

In order to see the actual depth of field, some cameras provide a preview button of depth of field. Press the button to reduce the aperture to the selected size, and the scene you see after shooting is the same as that recorded on the film (memory card).

composition

The name composition comes from western art, and there is a course called composition in western painting.

The composition of famous names is also called layout or quotient position in Chinese painting theory. In other words, photographic composition is transformed from artistic composition, which we can simply call framing.

Whether it is the layout in Chinese painting or the framing in photography, it only involves part of the composition, and it cannot contain the full meaning of composition. Therefore, it is more scientific and accurate to use the word "component" uniformly.

Sensitivity (ISO)

Indicates the exposure speed of photosensitive materials. Units are expressed in degrees or fixed. For example, "ISO 100/2 1" means a film with a fixed sensitivity of 100 degrees /2 1. The higher the sensitivity, the more sensitive the film is (that is, the less light is needed to shoot the same photo normally in the same shooting environment, that is, a higher shutter or a smaller aperture can be used).

Color temperature (color temperature)

Different pigments contained in different kinds of light are called "color temperature". The unit is "k". The color temperature we usually use is 5400 K-5600 K; The color temperatures that light types A and B can adapt to are 3400K and 3200K respectively. Therefore, different types of films should be selected according to the subject and environment, otherwise there will be color cast (unless the color temperature is corrected by color filter).

Understand white balance

White balance is a very important concept of digital camera. The so-called White Balance (white balance in English) is the restoration of white objects by digital cameras. There are many general white balance modes, which are suitable for different scenes, such as automatic white balance, tungsten wire white balance, fluorescent white balance, shadow white balance and so on.

Adjust white balance

Different digital cameras have different ways to adjust the white balance. You need to read the manual of the camera and learn how to change the white balance setting. Speaking of which, many digital cameras have automatic or semi-automatic white balance mode to help you.

Adjust the setting exposure.

The process by which light reaches the surface of a film and makes it sensitive. It should be noted that by exposure, we mean film exposure, which is a necessary process for us to obtain photos. Often depends on the combination of aperture and shutter, so there is the word exposure combination. For example, the shutter measured by the exposure meter is 1/30 seconds, and the aperture should be 5.6, so F5.6 and 1/30 seconds are an exposure combination.

Exposure compensation (exposure compensation)

Generally, exposure compensation is used in automatic or semi-automatic exposure mode. If it is a full manual exposure mode, exposure compensation is rarely used, because the amount of light entering can be changed by adjusting the shutter and aperture.

In the Gao Fancha environment with complex light and strong contrast, it is sometimes difficult to give consideration to the overall situation and achieve the expected results by using automatic exposure or shutter and aperture priority mode. At this point, the photographer needs to manually adjust the corresponding exposure parameters of the equipment, which is called exposure compensation, also known as EV. For beginners, exposure compensation is generally used for still life and scene shooting. This situation is suitable for calmly adjusting parameters and taking photos of different compensation schemes for selection. However, in the contrast picture, it is difficult to give full consideration to exposure compensation, and it is easy to lose sight of one thing and lose sight of another.

Noun interpretation

1, light ratio

Refers to the light reception ratio between the dark side and the bright side of the object under the illumination environment. The light ratio is of great significance to the contrast control of photos.

2. Brightness level

Refers to the specific position of lamps in three-dimensional space. Among them, there are surface lights, slap lights, platform pillar lights, foot lights, platform ceiling lights, ceiling lights gathering, ceiling lights flooding, sky lights, floor lights, side bridge lights, side lights, (hanging cage bench) chasing lights and so on.

3. focal length

Distance from the center of the lens to the focal point. It is also the distance from the center of the lens to the imaging plane such as the backplane or CCD in the camera.

4. Perspective

The angle between the lens center and the diagonal ends of the imaging plane is the lens angle. For the same imaging area, the shorter the focal length, the larger the viewing angle.

5. Lightness

The brightness of the lens is the amount of luminous flux. The larger the aperture, the greater the luminous flux and the smaller the brightness. Brightness is calculated as a multiple of the aperture coefficient. Brightness is one of the important factors that determine exposure.

third dimension

Through the processing of light, tone and color, the shape of the object is expressed in length, width and height, and then the main body in the three-dimensional space is reproduced on the plane to obtain the feeling of three-dimensional shape. Generally, side light and backlight are used for shooting.