What is the function of the wide-angle lens of a digital camera?
The main parameters of the optical lens and evaluation of the main parameters are focal length, field of view, object distance, aperture, shutter and so on. The most perfect evaluation of the lens than the MTF (Modulation Transfer Function). However, due to aberration (calibration reasons), each range of the lens has an MTF value. These ranges refer to: (1) the paraxial portion, (2) the off-axis portion, and (3) when the optical system has an asymmetric distortion, the two parts are sub-sections in different directions. Each part has its own corresponding MTF value for different radiation energy wavelength ranges. MTF is the most commonly used and optimal index of the imaging system, and it is also the optimal index to guide the integration of machine vision system.
????In the shooting of the distant movement scene, play a key role is the camera shutter speed, which is closely related with the composition, such as children, walking the characters generally more than 1 / 125S can, if the high-speed sports Of the images such as cars and other general in the 1 / 500-1 / 2000S, in general, to be able to shoot the angle to decide.
