TREN
FujiFilm GFX 100 read noise vs ISO
The FujiFilm GFX 100 was measured at 26 ISO settings from ISO 50 to ISO 102400. Values are Bill Claff's (Photons to Photos) direct measurements from raw files.
At base ISO (100) read noise is 5.39 DN, or 3.4 electrons at the sensor. From ISO 2000 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 41,534 electrons; unity gain is around ISO 60.
FujiFilm GFX 100 read noise table
| ISO | Read noise (DN) | log₂ |
|---|---|---|
| 50 | ○ 3.580 | 1.84 |
| 100 | 5.389 | 2.43 |
| 125 | 6.635 | 2.73 |
| 160 | 8.112 | 3.02 |
| 200 | 8.398 | 3.07 |
| 250 | 10.126 | 3.34 |
| 320 | 12.906 | 3.69 |
| 400 | 15.780 | 3.98 |
| 500 | 10.056 | 3.33 |
| 640 | 12.042 | 3.59 |
| 800 | 14.723 | 3.88 |
| 1000 | 18.507 | 4.21 |
| 1250 | 23.588 | 4.56 |
| 1600 | 29.243 | 4.87 |
| 2000 | 35.753 | 5.16 |
| 2500 | 43.411 | 5.44 |
| 3200 | 53.076 | 5.73 |
| 4000 | 66.257 | 6.05 |
| 5000 | 83.286 | 6.38 |
| 6400 | 103.250 | 6.69 |
| 8000 | 133.436 | 7.06 |
| 10000 | 162.017 | 7.34 |
| 12800 | 191.341 | 7.58 |
| 25600 | ○ 282.088 | 8.14 |
| 51200 | ▼ 308.687 | 8.27 |
| 102400 | ▼ 304.437 | 8.25 |