|產品類別||Camera lens filters|
|生產廠||B + W|
This b+w neutral density filter reduces the light by six f-stops. With this filter & without changing the f-stop, a shutter speed of 160 s is changed to a full second, thus requiring the use of a tripod. Flowing water is rendered as flowing in the photo, & people moving in streets are dissolved in unsharpness or become invisible. Because of its higher transmission in the red beyond 660 nm, this filter brings a slightly warm tone to color photographs. If this effect is undesirable, a b+w uv-ir-blocking filter 486 in front of the neutral density filter (not behind it) remedies that situation. The filter factor is 64x.