TREN
Nikon D4S read noise vs ISO
The Nikon D4S was measured at 34 ISO settings from ISO 50 to ISO 409600. Values are Bill Claff's (Photons to Photos) direct measurements from raw files.
At base ISO (100) read noise is 2.07 DN, or 15 electrons at the sensor. From ISO 6400 up the camera is effectively ISO-invariant: raising ISO further doesn't meaningfully lower shadow noise. Settings above ISO 12800 don't change analog gain (digital push). Full well at base ISO is about 113,218 electrons; unity gain is around ISO 730.
Nikon D4S read noise table
| ISO | Read noise (DN) | log₂ |
|---|---|---|
| 50 | ○ 2.129 | 1.09 |
| 64 | ○ 2.114 | 1.08 |
| 80 | ○ 2.099 | 1.07 |
| 100 | 2.071 | 1.05 |
| 125 | 2.173 | 1.12 |
| 160 | 2.346 | 1.23 |
| 200 | 2.056 | 1.04 |
| 250 | 2.204 | 1.14 |
| 320 | 2.378 | 1.25 |
| 400 | 2.497 | 1.32 |
| 500 | 2.713 | 1.44 |
| 640 | 3.053 | 1.61 |
| 800 | 3.411 | 1.77 |
| 1000 | 4.000 | 2.00 |
| 1250 | 4.659 | 2.22 |
| 1600 | 5.816 | 2.54 |
| 2000 | 6.727 | 2.75 |
| 2500 | 7.945 | 2.99 |
| 3200 | 9.646 | 3.27 |
| 4000 | 11.876 | 3.57 |
| 5000 | 15.242 | 3.93 |
| 6400 | 16.679 | 4.06 |
| 8000 | 21.556 | 4.43 |
| 10000 | 24.590 | 4.62 |
| 12800 | 31.125 | 4.96 |
| 16000 | ▲ 39.124 | 5.29 |
| 20000 | ▲ 51.625 | 5.69 |
| 25600 | ▲ 63.558 | 5.99 |
| 32000 | ▲ 75.584 | 6.24 |
| 40000 | ▲ 94.353 | 6.56 |
| 51200 | ▲ 119.428 | 6.90 |
| 102400 | ▲ 240.518 | 7.91 |
| 204800 | ▲ 464.650 | 8.86 |
| 409600 | ▲ 797.865 | 9.64 |