Hoya 49mm Neutral Density x400 (ND) 2.7 Hoya Multi-Coated (HMC) Glass Filter

Photographing solar eclipses and ultra-bright light sources can be extremely dangerous. This filter reduces light values by 9 stops to less than 1/500th of its original intensity and allows safe photography. It can also be used to achieve super slow shutter speeds in daylight to render moving subjects invisible.

Neutral Density filters have four main uses

To enable slow shutter speeds to be used, especially with high speed films, to record movement in subjects such as waterfalls, clouds, or cars

To decrease depth of field by allowing wider apertures to be used, which helps separate subjects from their background

To decrease the effective ISO of high speed film (above ISO 400) and allow it to be used outdoors in bright situations

To allow cine and video cameras (which have fixed shutter speeds) to film subjects such as snow, sand or other bright scenes which could cause overexposure

Neutral Density Factors

2x = ND.3 (exposure adjustment = 1 stop, reduces ISO 1/2)

4x = ND.6 (exposure adjustment = 2 stops, reduces ISO 1/4)

8x = ND.9 (exposure adjustment = 3 stops, reduces ISO 1/8)

As one of the premier filter manufacturers, Hoya filters continue to made from quality glass assuring the photographer clear, sharp and accurate images

Hoya filters consistently provide even color all the way through the filter; All surfaces are ground and polished to specific thickness and tolerances

Even non-multi-coated Hoya filters have one layer of anti-reflective coating applied to each surface of the glass; Hoya's single layer coating decreases light reflection off the surface from approx. 9% to an average of 4-5%