What is Deep Fusion on the iPhone?

Deep Fusion uses computational photography to combine several image captures into one high-fidelity photo. The resulting photos feature a higher level of detail, less noise, and improved textures.

Multiple exposures are taken of the same scene and analyzed by Apple's Bionic Neural Engine. Short and long exposures are combined and processed pixel-by-pixel to optimize detail, color tone, and luminosity. Apple called Deep Fusion "mad science" at the iPhone 11 keynote event.