Which of the following is not a depth cue according to SPOTFM?

• A. Size
• B. Perspective
• C. Occlusion
• D. Color constancy

Answer: (D)

Depth cues in SPOTFM are cues that help us judge distance from a single view. Size signals distance because, if you know how big something normally is, a smaller image implies it is farther away. Perspective refers to how parallel lines appear to converge with distance, giving a sense of depth. Occlusion provides depth ordering when one object hides part of another—the hidden part must be behind. Color constancy, by contrast, is about keeping perceived color stable under different lighting, not about judging how far away something is. So it doesn’t function as a depth cue in SPOTFM, making it the correct choice.