iFixit Teardown Exposes iPhone 18 Pro's Magnetic Variable Aperture
iFixit has disassembled the main camera of the iPhone 18 Pro and iPhone 18 Pro Max to document the inner workings of the variable aperture lens. The article, titled Inside the Tiny Unfixable Eye: iPhone 18 Pro and Pro Max Teardown and authored by Elizabeth Chamberlain, was published on September 20, 2026 iFixit.
The subject is the 48MP Fusion main camera with variable aperture and software-adjustable shutter speed. Light control comes from an adjustable mechanical iris that opens and closes magnetically to meter light to the sensor. The iris uses six overlapping leaf-like blades, each about as thin as a human hair. Apple fit that stack into the same main camera footprint used by iPhone 17 Pro series models.
Control is discrete, not continuous. The camera app offers four preset apertures, from widest to narrowest: ƒ/1.48, ƒ/1.8, ƒ/2.8, and ƒ/4.0. Apple describes the 48MP Fusion Main camera with variable aperture as the most advanced camera Apple has ever made, and notes variable aperture on iPhone 18 Pro for the first time Apple. The company states the system automatically adjusts for depth of field and lighting, and states it offers better-quality low-light photography and crisper details.
iFixit called the lens "a feat of precision engineering." That precision comes with a service penalty. The firm assessed the mechanism as close to impossible to repair, requiring specialist tools, techniques and knowledge. In practice, a failure in the iris means replacement of the entire camera assembly. The tradeoff is softened at the module level. The camera assembly itself is easy to access. For reference, the iPhone 17 Pro camera assembly costs $249 The Verge.
The teardown also flagged a separate concern around the display. The screen's plastic frame tore apart on three of the four iPhone 18 Pro phones iFixit opened. The finding forms part of a wider exploration of a potential issue involving display repairs.
Early photographic payoff looks modest. The Verge's iPhone 18 Pro review found the variable aperture lens made a generally marginal improvement on overall photography. The Pro models also carry a 48MP Fusion Ultra Wide camera that captures wider fields of view and enables macro photography.
The broader context here is a familiar engineering bargain in compact systems. Magnetic actuation and hair-thin leaves allow mechanical aperture control without expanding the module, which preserves board and battery volume. It also pushes service from component repair to module swap. In this author's view, that is a rational outcome rather than a design lapse. Miniature diaphragms were never bench-serviceable parts. Worth flagging for professionals is what this enables next: mechanical exposure control paired with computational pipelines gives engineers an additional physical variable for depth of field and low-light capture, even if the first-generation gain is incremental.
