iPhone 18 Pro's variable aperture explained: what it means for photos

Apple has introduced its first mechanical variable aperture in the iPhone 18 Pro and Pro Max, a rare feature for smartphones that allows users to manually adjust light intake from f/1.48 to f/4.0. The six-blade mechanism, thinner than a human hair, provides greater control over exposure and depth of field, aiding indoor portraits, astrophotography, and video with longer shutter speeds. It also improves sharpness by using the lens's central area. While offering more creative control, the feature's impact is limited by the smaller sensor compared to 1-inch competitors like the Xiaomi 17 Ultra. Computational photography remains the primary driver of image quality improvements.