Description
ND400 absorptive neutral density filters have an optical density of 4.0, meaning that they transmit an average of 0.01% of the visible light. Surprisingly, this amount of light passing though the filter is easily detectable by the human eye. Because the glass substrate is absorbing 99.9% of the light that passes into the filter, it is not recommended that these filters be used in laser applications or immediately in front of high wattage lamps.
- Useful Range: 425 to 675 nm
- Optical Density: 4.0
- Transmission: 0.01%
- Tolerance: +/- 0.003%
- Surface Quality: 40/20
