The white space within the photographic frame differs from the painting, forming a high-key blank (white space) and a low-key blank space (black space), as well as a medium-gray white space (gray space) in between. Black blank space is suitable for expressing emotions such as coldness, perseverance, seriousness and solemnity; while gray blank space is suitable for expressing the meaning of dullness, depression, helplessness and loneliness; white blank space is suitable for expressing feelings such as ease, brightness, enthusiasm and unrestrainedness.