Well-known insider Ice Universe said it’s 100%: The S23 Ultra’s 200-megapixel main camera will have a 1/1.3-inch size, 0.6 micron pixel size and f/1.7 aperture.
For reference, the 108-megapixel S22 Ultra has a 1/1.33-inch sensor with 0.8µm pixel size and f/1.8 aperture. Ice Universe points out that the 200MP camera is only slightly larger than the iPhone 14 Pro camera and even smaller than other Android flagships in 2023.
Source: Ferra
