Which distortion is typically associated with minus-powered lenses?

• A. Barrel
• B. Pincushion
• C. Distortion
• D. None

Answer: (A)

Geometric distortion is about how magnification changes across the field, so straight lines bend rather than staying straight. Minus-powered lenses tend to produce barrel distortion, where lines bow outward as you look toward the edges of the lens. This happens because diverging rays from a negative lens cause peripheral magnification to differ from the center, making edge features appear stretched outward. In contrast, plus-powered lenses more often lead to pincushion distortion, where lines bow inward toward the center due to the opposite magnification pattern. The other options don’t specify the common peripheral distortion tied to negative power, and “None” would ignore this typical optical artifact.