TREN
Canon EOS 400D read noise vs ISO
The Canon EOS 400D was measured at 5 ISO settings from ISO 100 to ISO 1600. Values were derived by Bill Claff from DxOMark lab data.
At base ISO (100) read noise is 2.30 DN. From ISO 800 up the camera is effectively ISO-invariant: raising ISO further doesn't meaningfully lower shadow noise.
Canon EOS 400D read noise table
| ISO | Read noise (DN) | log₂ |
|---|---|---|
| 100 | 2.297 | 1.20 |
| 200 | 2.462 | 1.30 |
| 400 | 3.317 | 1.73 |
| 800 | 5.696 | 2.51 |
| 1600 | 9.714 | 3.28 |