Samsung Galaxy S7 (IMX260) vs Samsung GX-20: read noise comparison

The Samsung Galaxy S7 (IMX260) was measured at 12 ISO settings from ISO 50 to ISO 800. Values are Bill Claff's (Photons to Photos) direct measurements from raw files.

At base ISO (50) read noise is 1.42 DN, or 8.9 electrons at the sensor. From ISO 160 up the camera is effectively ISO-invariant: raising ISO further doesn't meaningfully lower shadow noise. Settings above ISO 320 don't change analog gain (digital push). Full well at base ISO is about 6,432 electrons; unity gain is around ISO 310.

The Samsung GX-20 was measured at 7 ISO settings from ISO 100 to ISO 6400. Values were derived by Bill Claff from DxOMark lab data.

At base ISO (100) read noise is 2.53 DN. Read noise keeps falling across the measured range, so the camera isn't fully ISO-invariant there.