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What Do You Think? The eyes and brain estimate distance by the direction the eyes look to focus on an object. If the object is very distant, like a star, the two eyes point in the same direction, since the small distance between them is insignificant. In a practical sense, this is also true for objects more distant than about 20 m away. If the object is very close, then the eyes must turn toward each other. If the object is 30 cm away, then the difference in direction the eyes look is about 20° (assuming the eyes are 10 cm apart). |