Kodak 4 x 4" Carbon Neutral Density (ND) 0.9 Wratten 2 Gel Filter

• Carbon Neutral Density Filter are used to reduce the intensity of light by a definite ratio, without affecting the tonal rendition of colors; improves neutrality in the UV and IR fields.

Wratten 2 Improvements

• More rigid/durable

• Easier to handle

• Color consistent today, and 6 months from now as well

• Wratten 2 Optical Filters are less sensitive to humidity, less prone to static cling.

• Fingerprint removal is also easier

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

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

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

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

• ND 1.8 (exposure adjustment = approx. 6 stops, transmits 1% of light,)

• ND 3.0 (exposure adjustment = 10 stops, transmits 0.1% of light)

• ND 4.0 (exposure adjustment = 13-2/3 stops, transmits 0.01% of light)

• ND 6.0 = (exposure adjustment = approx. 20 stops)