ND Filter Calculator
Calculate shutter speed with neutral density filters.
Find the right ND filter for long exposure photography.
Adjusted Exposure
ND (Neutral Density) filters reduce light entering the lens, allowing longer exposures. They are essential for silky water, motion blur, and shooting wide open in bright light.
ND filter stops and factors:
| Filter | Stops | Factor | Light Reduction |
|---|---|---|---|
| ND2 | 1 | 2× | 50% |
| ND4 | 2 | 4× | 75% |
| ND8 | 3 | 8× | 87.5% |
| ND16 | 4 | 16× | 93.75% |
| ND64 | 6 | 64× | 98.4% |
| ND256 | 8 | 256× | 99.6% |
| ND1000 | 10 | 1024× | 99.9% |
The formula:
New Shutter Speed = Base Shutter Speed × Filter Factor
Example: 1/250s with ND1000 (10 stops) = 1/250 × 1024 = ~4 seconds
Common long exposure targets:
- Silky waterfalls: 0.5–2 seconds
- Smooth water: 15–30 seconds
- Cloud streaks: 60–300 seconds (1–5 minutes)
- Light trails: 10–30 seconds