Abruzzi Photography: Shutter Speed

Shutter is a device that allows light to irradiate the film in a precise time period, and it is a structure used by the camera to control the effective exposure time of the photosensitive film. It is an important part of the camera, and its structure, form and function are important factors to measure the grade of the camera.

Shutter speed is in seconds. The highest shutter speed of professional 135 cameras reaches116000 seconds. Common shutter speeds are:11/21/41/811/301/65438+. The shutter speed exposure of two adjacent stages is twice different, and we often say that the difference is one stage. For example, the exposure of1/60s is twice that of1125s, that is,1125s is one step slower or one step lower.

As for the common B shutter function of SLR cameras, you can freely decide the length of exposure time, making shooting more flexible.

After we decide the shutter speed ourselves, the camera metering system will automatically select the appropriate aperture F value (which can be a stepless F value) according to the light conditions at that time. Digital cameras with exposure mode dial usually engrave the letter "S" on the dial to represent the shutter priority mode.

Generally speaking, the shutter speed to prevent hand shake is "1/ lens focal length (seconds)", which is an empirical value, also called safety shutter. For example, the camera of 135 uses a lens with a focal length of 85mm, and the shutter speed that can effectively and clearly shoot the subject should not be lower than 1/85 seconds. By analogy, when the focal length of the lens is 200mm, the shutter speed should be set above 1/200 seconds. It should be noted that if a common digital camera (DC) or a non-Quan Huafu digital SLR camera is used, the focal length should be converted to that of 135 camera. If a 50mm lens is used on the Canon EOS 400D, the safety shutter is1(50×1.6) =1/80 seconds. Moreover, the safety shutter will generally improve the success rate of shooting, but the photos taken at a shutter speed lower than the safety shutter may not necessarily fail.

Shutter priority mode is suitable for photography that needs to control the shutter. Shutter priority is mostly used to shoot moving objects, such as sports, moving vehicles, waterfalls, flying objects, fireworks, water droplets and so on.

Shutter selection for common scenes:

1) chilled water: over 1/4000s.

2) Freezing birds in the air:1/more than 2000s.

3) Shooting sports theme: 1/500s or more.

4) Freeze most slow-moving subjects: 1/250 s or more.

5) Shoot the silky waterfall:1s.

6) Shoot the light and shadow track of urban traffic: 10s.

Using high-speed shutter can condense action, which is suitable for shooting moving objects and can easily capture fast moving targets.

Used to photograph moving objects, especially in sports shooting. When shooting a moving object, the subject is blurred, mostly because the shutter speed is not fast enough. In this case, you can use the shutter priority mode, roughly determine a shutter value, and then shoot. And the motion of the object is generally regular, then the shutter value can also be roughly estimated. For example, the shutter speed for photographing pedestrians is only1125 seconds, while it takes11000 seconds for photographing falling water droplets. The automatic metering system will calculate the exposure value, and then automatically determine how much aperture to use according to the shutter speed you choose.

1) After the camera is fixed, the moving object will be blurred due to the slow shutter speed. The clear background (still life) can further set off the dynamic theme.

2) Let the camera translate or shift along the direction of the object movement, which is just the opposite of the first method. The background will become quite vague, and the subject will be a little vague but clear, separating the theme from the background.

3) The whole photo is blurred, and then the camera is shaken quickly.

Using a fast shutter, the car is photographed as a dot.

Using a slow shutter, you can turn a moving vehicle into a light beam and shoot a silky water flow effect.

Reference: Photographic textbooks of New York Institute of Photography, USA