Panasonic Lumix DC-GX800 vs Panasonic Lumix DC-S1: read noise comparison

The Panasonic Lumix DC-GX800 was measured at 9 ISO settings from ISO 100 to ISO 25600. Values were derived by Bill Claff from DxOMark lab data.

At base ISO (100) read noise is 0.47 DN. From ISO 6400 up the camera is effectively ISO-invariant: raising ISO further doesn't meaningfully lower shadow noise.

The Panasonic Lumix DC-S1 was measured at 37 ISO settings from ISO 50 to ISO 204800. Values are Bill Claff's (Photons to Photos) direct measurements from raw files.

At base ISO (100) read noise is 1.14 DN, or 6.9 electrons at the sensor. A second gain (dual gain) kicks in at ISO 800, cutting input-referred read noise by about 1.7 stop. From ISO 4000 up the camera is effectively ISO-invariant: raising ISO further doesn't meaningfully lower shadow noise. Settings above ISO 51200 don't change analog gain (digital push). Full well at base ISO is about 95,590 electrons; unity gain is around ISO 600.