TREN
Olympus E-5 read noise vs ISO
The Olympus E-5 was measured at 19 ISO settings from ISO 100 to ISO 6400. Values are Bill Claff's (Photons to Photos) direct measurements from raw files.
At base ISO (200) read noise is 3.58 DN, or 15.8 electrons at the sensor. From ISO 800 up the camera is effectively ISO-invariant: raising ISO further doesn't meaningfully lower shadow noise. Full well at base ISO is about 17,692 electrons; unity gain is around ISO 880.
Olympus E-5 read noise table
| ISO | Read noise (DN) | log₂ |
|---|---|---|
| 100 | ○ 3.555 | 1.83 |
| 125 | ○ 4.500 | 2.17 |
| 160 | ○ 5.736 | 2.52 |
| 200 | 3.580 | 1.84 |
| 250 | 4.469 | 2.16 |
| 320 | 5.736 | 2.52 |
| 400 | 4.993 | 2.32 |
| 500 | 6.364 | 2.67 |
| 640 | 8.056 | 3.01 |
| 800 | 8.112 | 3.02 |
| 1000 | 10.411 | 3.38 |
| 1250 | 13.086 | 3.71 |
| 1600 | 16.336 | 4.03 |
| 2000 | 20.393 | 4.35 |
| 2500 | 26.173 | 4.71 |
| 3200 | 31.779 | 4.99 |
| 4000 | 40.504 | 5.34 |
| 5000 | 49.522 | 5.63 |
| 6400 | 60.129 | 5.91 |