Pentax Q10 read noise vs ISO

The Pentax Q10 was measured at 19 ISO settings from ISO 100 to ISO 6400. Values are Bill Claff's (Photons to Photos) direct measurements from raw files.

At base ISO (100) read noise is 0.86 DN, or 2.7 electrons at the sensor. From ISO 1000 up the camera is effectively ISO-invariant: raising ISO further doesn't meaningfully lower shadow noise. Full well at base ISO is about 13,070 electrons; unity gain is around ISO 320.