Baader Planetarium 2458321 2-Inch Neutral Density Filter - Black/Glass

2" neutral density filter with optical density 0.6, 25% transmission, 4x reduction factor. When looking at the sun, only use as an additional filter! If you need to reduce overexposure and wish to use a filter far in front of the focal point (e.g. in front of binoculars), the neutral filter is just right. The fine optical polish of our filters means that even with a filter position 20-30 cm before the focal point there is no loss of sharpness with large magnifications. Baader Neutral Density Filter 2 Inch (OD 0.6 T=25%)