Depth perception is the ability to perceive distance to objects in the world using the visual system and visual perception. It is a major factor in perceiving the world in three dimensions. Depth perception happens primarily due to stereopsis and accommodation of the eye.
Shots at different distances
The horizon line is at the height of the armrests.
View from a window on the 2nd floor of a house
Earth curvature
The visual system is the physiological basis of visual perception. The system detects, transduces and interprets information concerning light within the visible range to construct an image and build a mental model of the surrounding environment. The visual system is associated with the eye and functionally divided into the optical system and the neural system.
The eye is the sensory organ of the visual system. The iris, pupil, and sclera are visible
Representation of optic pathways from each of the 4 quadrants of view for both eyes simultaneously
S. Ramón y Cajal, Structure of the Mammalian Retina, 1900
Information flow from the eyes (top), crossing at the optic chiasma, joining left and right eye information in the optic tract, and layering left and right visual stimuli in the lateral geniculate nucleus. V1 in red at bottom of image. (1543 image from Andreas Vesalius' Fabrica)