Nikon D780 vs Nikon D80: read noise comparison

The Nikon D780 was measured at 35 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 1.38 DN, or 7.8 electrons at the sensor. A second gain (dual gain) kicks in at ISO 800, cutting input-referred read noise by about 1.5 stop. From ISO 12800 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 87,028 electrons; unity gain is around ISO 570.

The Nikon D80 was measured at 16 ISO settings from ISO 100 to ISO 3200. Values are Bill Claff's (Photons to Photos) direct measurements from raw files.

At base ISO (100) read noise is 2.39 DN, or 15.2 electrons at the sensor. From ISO 100 up the camera is effectively ISO-invariant: raising ISO further doesn't meaningfully lower shadow noise. Settings above ISO 640 don't change analog gain (digital push). Full well at base ISO is about 25,971 electrons; unity gain is around ISO 630.