What is Parallax ?

Question

In Ray Optics.

Answer 1

Parallax, or more accurately motion parallax (Greek: παραλλαγή (parallagé) = alteration) is the change of angular position of two stationary points relative to each other as seen by an observer, due to the motion of an observer. Simply put, it is the apparent shift of an object against a background due to a change in observer position.

Introduction
This parallax is often thought of as the 'apparent motion' of an object against a distant background because of a perspective shift, as seen in Figure 1. When viewed from Viewpoint A, the object appears to be closer than the blue square. When the viewpoint is changed to Viewpoint B, the object appears to have moved in front of the red square. It is most commonly used in astronomy.

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Answer 2

Optical parallax: the apparent displacement in position undergone by an object when viewed by either eye singly.

Answer 3

Parallax causes adjacent pictures for a panorama to differ in ways that prevents them from being stitched together perfectly. It can cause ghosting, blurring, or even prevent stitching software from being able to work out where to position the pictures to be able to stitch them together.

Answer 4

a pair of laagers
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