The role of the camera shading ring
1. Blurred background
In addition to changing the shutter speed, the visor can also change the depth of field. First, let's get to know the concept of depth of field.
Depth of field: There is a certain length of space in front of the lens (before and after the focus adjustment). When the subject is located in this space, the image on the negative film is exactly between the two circles of confusion before and after the focus. The length of the space where the subject is located is called the depth of field.
2, SLR cameras that affect the image quality
Compared with consumer-grade digital cameras, the lens of a SLR camera adopts a more complex optical lens structure and a larger optical lens, and the impact of different sizes of iris on the in-focus image quality of the SLR lens is generally greater.
3, affect the image quality DC
In theory, the size of the visor has nothing to do with the sharpness of the image in the camera's focus, but because the imaging principle of the optical lens and the accuracy of the glass refraction cannot be 100% consistent with the theoretical value, the image quality under different apertures still has a certain degree The difference.
Compared with the optical lens of a SLR camera, the aperture range of a DC lens is much smaller, especially the minimum aperture value is generally F8.0.
At the same time, for most DCs, whether at the wide-angle end or the telephoto end of the camera, the maximum aperture (that is, the aperture when the F value is the smallest) is the aperture with the best focal sharpness, which is what everyone calls it. The best aperture.