Apple iPhone 14 Pro Max read noise vs ISO

The Apple iPhone 14 Pro Max was measured at 23 ISO settings from ISO 64 to ISO 10000. Values are Bill Claff's (Photons to Photos) direct measurements from raw files.

At base ISO (64) read noise is 1.61 DN, or 5 electrons at the sensor. From ISO 400 up the camera is effectively ISO-invariant: raising ISO further doesn't meaningfully lower shadow noise. Settings above ISO 500 don't change analog gain (digital push). Full well at base ISO is about 11,146 electrons; unity gain is around ISO 200.