Size constancy: Size constancy is closely related to constant perception and refers specifically to perceiving an object's size as unchanged despite variations in its retinal image caused by different distances.
Visual illusions: Visual illusions are perceptual distortions that can challenge our ability for constant perception by creating misleading cues about an object's size or distance.
Depth cues: Depth cues are visual cues that help us perceive depth and distance accurately. Understanding depth cues can aid in maintaining constant perception of an object's size across different distances.