ND filter naming chart#
| Factor name | Density | Stops | Transmission | Time × |
|---|---|---|---|---|
| ND2 | ND 0.3 | 1 | 50% | ×2 |
| ND4 | ND 0.6 | 2 | 25% | ×4 |
| ND8 | ND 0.9 | 3 | 12.5% | ×8 |
| ND16 | ND 1.2 | 4 | 6.25% | ×16 |
| ND32 | ND 1.5 | 5 | 3.125% | ×32 |
| ND64 | ND 1.8 | 6 | 1.562% | ×64 |
| ND128 | ND 2.1 | 7 | 0.7812% | ×128 |
| ND256 | ND 2.4 | 8 | 0.3906% | ×256 |
| ND512 | ND 2.7 | 9 | 0.1953% | ×512 |
| ND1000 | ND 3.0 | 10 | 0.09766% | ×1,024 |
| ND8000 | ND 3.9 | 13 | 0.01221% | ×8,192 |
| ND32000 | ND 4.5 | 15 | 0.003052% | ×32,768 |
| ND64000 | ND 4.8 | 16 | 0.001526% | ×65,536 |
| ND1000000 | ND 6.0 | 20 | 9.537e-05% | ×1,048,576 |
ND filter calculator#
Shutter speed with filter—
Light reduction—
0:00
Three ways ND filters are labelled#
Manufacturers use three equivalent scales: the factor (ND8 = 1/8 of the light), the optical density (ND 0.9 = 10−0.9) and stops (3 stops). Each stop halves the light, and each 0.3 of density equals one stop.
Last updated October 03, 2026 · How we calculate · Sources