If it is an APS-C SLR, it is recommended to use a lens such as 35mmf2.8 (this focal length distortion is the smallest and closest to human vision).

Taking the fixed focus parameter of 35mmf2.8 as an example, the shutter is guaranteed to be 1/35, and the aperture is reduced to f4. Optimizing the aperture can ensure the sharpness of the focus and a certain background blur. The lowest sensitivity is 100, or even lower. Let the picture quality be the best. Use light to make the exposure of this parameter accurate. good