Which distortion types are associated with pin cushion and barrel effects?

The pin cushion and barrel effects are specific types of geometric distortion that occur when light rays are bent in a way that causes straight lines in the subject to appear curved in the image.

In the case of the barrel distortion, straight lines bulge outward away from the center of the image, resembling the shape of a barrel. This typically happens with wide-angle lenses. Conversely, pin cushion distortion occurs when straight lines are pinched toward the center of the image, which is often seen in telephoto lenses. Both distortions are directly related to the geometry of the lens and how it projects an image onto the sensor or film.

Recognizing these effects as geometric distortions is vital in fields such as photography and optics, as they influence the accuracy of image representation. Understanding this concept allows opticians and optical technicians to better choose and design corrective lenses and systems to minimize these effects, ensuring clearer and more accurate visual perceptions for clients.