What does the big aperture of the camera mean?

Large aperture refers to the lens of a camera, which is positioned at the professional level or quasi-professional level, and the workmanship is much better than the general lens.

In the case of the same frame and under the same conditions, the same level of aperture, the same luminous flux and the same depth of field. When the lens takes a picture, the lens diameter cannot be changed at will, but the luminous flux can be controlled by adding a polygonal or circular variable aperture grating inside the lens.

The exposure of the camera at the same sensitivity is determined by the aperture size (aperture F value) and shutter speed. Aperture f value = lens focal length/lens aperture diameter, that is, the smaller the aperture f value, the larger the aperture, and the greater the light input. So you can increase the aperture to increase the shutter speed, or decrease the aperture to decrease the shutter speed.

Extended data

Large aperture lenses usually perform well in poor light. A series of lenses called "night mirrors" in the field of SLR cameras, such as Nikon's Noct 58mm/F 1.2 and Leica's Noctilux-M50mm/F0.95aph night lenses, all have large apertures.

Under the same focal length, the larger the aperture, that is, the smaller the F value, the more obvious the blur effect of the background and the shallower the depth of field. Therefore, if you want to take a photo with a blurred background, try to use a large aperture at the same focal length.

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