Your portrait must be within the frame; when sampling, as long as the face is within the scope of the mirror, it is possible that the line of sight is parallel or low toward the center of the mirror. Please keep the face facing the mirror at a distance of about 30-80cm from the attendance machine. Keep your eyes on the center of the mirror, slowly move the face back and forth, and keep the sample natural. Try to keep the sampling environment consistent with the attendance environment during sampling. It is recommended to sample at the place where the attendance machine is placed. Please keep your expression natural, avoid closing your eyes, squinting, covering your eyes, and do not wear glasses when taking samples and attendance. This will facilitate faster attendance. Do not use near windows that are exposed to sunlight.