Hasselblad X2D II-100c read noise vs ISO

The Hasselblad X2D II-100c was measured at 10 ISO settings from ISO 50 to ISO 25600. Values are Bill Claff's (Photons to Photos) direct measurements from raw files.

At base ISO (50) read noise is 4.17 DN, or 3.8 electrons at the sensor. A second gain (dual gain) kicks in at ISO 200, cutting input-referred read noise by about 1.5 stop. From ISO 3200 up the camera is effectively ISO-invariant: raising ISO further doesn't meaningfully lower shadow noise. Settings above ISO 6400 don't change analog gain (digital push). Full well at base ISO is about 55,739 electrons; unity gain is around ISO 50.