Panasonic Lumix G9 II read noise vs ISO

The Panasonic Lumix G9 II (Lumix DC-G9M2) was measured at 28 ISO settings from ISO 50 to ISO 25600. Values are Bill Claff's (Photons to Photos) direct measurements from raw files.

At base ISO (100) read noise is 9.78 DN, or 2.5 electrons at the sensor. From ISO 3200 up the camera is effectively ISO-invariant: raising ISO further doesn't meaningfully lower shadow noise. Settings above ISO 12800 don't change analog gain (digital push). Full well at base ISO is about 16,380 electrons; unity gain is around ISO 30.