TREN
Apple iPhone 7 read noise vs ISO
The Apple iPhone 7 was measured at 19 ISO settings from ISO 25 to ISO 1600. Values are Bill Claff's (Photons to Photos) direct measurements from raw files.
At base ISO (25) read noise is 2.39 DN, or 1.6 electrons at the sensor. From ISO 160 up the camera is effectively ISO-invariant: raising ISO further doesn't meaningfully lower shadow noise. Settings above ISO 200 don't change analog gain (digital push). Full well at base ISO is about 2,340 electrons; unity gain is around ISO 20.
Apple iPhone 7 read noise table
| ISO | Read noise (DN) | log₂ |
|---|---|---|
| 25 | 2.395 | 1.26 |
| 32 | 2.676 | 1.42 |
| 40 | 2.990 | 1.58 |
| 50 | 3.434 | 1.78 |
| 64 | 3.864 | 1.95 |
| 80 | 4.500 | 2.17 |
| 100 | 5.540 | 2.47 |
| 125 | 6.498 | 2.70 |
| 160 | 7.727 | 2.95 |
| 200 | 8.340 | 3.06 |
| 250 | ○ 8.282 | 3.05 |
| 320 | ○ 8.515 | 3.09 |
| 400 | ○ 8.340 | 3.06 |
| 500 | ○ 8.456 | 3.08 |
| 640 | ○ 8.398 | 3.07 |
| 800 | ○ 8.398 | 3.07 |
| 1000 | ○ 8.456 | 3.08 |
| 1250 | ○ 8.456 | 3.08 |
| 1600 | ○ 8.340 | 3.06 |