Which distortion is typically associated with plus-powered lenses?

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

Answer: (B)

Distortion describes a change in how shapes are mapped when viewed through a lens, specifically how magnification varies across the field. Plus-powered lenses (convex lenses) tend to magnify the center of the field more than the edges, so straight lines in a grid or chart appear to bow inward toward the center. That inward bending is called pincushion distortion. In contrast, minus-powered lenses (concave lenses) usually produce barrel distortion, where lines bend outward toward the edges. So the distortion typically associated with plus-powered lenses is pincushion.