What can the safety shutter speed be?

The calculation method of general safety shutter is the reciprocal of focal length, that is, 1/ focal length.

For example, if you use a 200mm lens, the safety shutter is 1/200. But in fact, we generally say that the safety shutter is not afraid of any lens as long as it can guarantee 1/250 seconds, while the basic safety shutter is 1/50.

1. What is a safety shutter?

Safety shutter means that the camera usually performs the exposure process at the moment when 1/30s or 1/60s camera clicks. If this time is less than 1/60s, it is easy to blur the picture due to hand shaking.

When shooting a movie, the film is often blurred, which is often because the shutter speed during shooting does not reach the safe shutter speed, and hand jitter will be directly reflected in the photo, leading to false shooting. Simply put, the safety shutter is a boundary line of the slowest shutter that usually makes the film not blurred. In the actual shooting process, there is no strict numerical calculation. When using a certain shutter, as long as the film is not blurred, this shutter speed can be called a safety shutter.

Second, the shutter description

It is a device that prevents light from reaching the front of the camera. Generally speaking, the larger the shutter time range, the better. Low seconds is suitable for shooting moving objects, so a camera emphasizes that the shutter can reach116000 seconds at the earliest, which can easily capture fast moving targets. However, when shooting traffic at night, the shutter time will be lengthened, and the silky water flow effect in ordinary photos can only be photographed with a slow shutter.

As for the common B shutter function of SLR cameras, although you can freely decide the length of exposure time and have high shooting flexibility, most consumer digital cameras can't support it at present, and can provide the default values of slower speed such as 2 seconds, 8 seconds, 16 seconds at most.

1, shutter delay time

When the camera does not use the focus lock function and ensures that it is in the auto-focus working state, the time from pressing the shutter release button to starting exposure is called shutter lag time.

2. Shutter Prerequisite Exposure Mode

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 equipped with exposure mode dial usually engrave the letter "S" on the dial, which stands for the required shutter mode. Shutter priority mode is suitable for photography that needs to control the shutter. High-speed shutter can condense action, and slow shutter can turn moving vehicles into light beams.

3. Shutter delay

When the camera presses the shutter, the time required for the camera to focus automatically, measure light, calculate exposure, select appropriate exposure combination, calculate and store data is called shutter delay.