.6 Grade Neutral Density Filter.

Neutral density glass filters (also known as ND filters) produce a grey neutral tone and are used to reduce light, enabling more control over exposure and depth of field without affecting colour or contrast.

ND filters are especially useful in bright light conditions to avoid overexposure. When using wider lenses they adjust exposure correctly, allowing for reduced depth of field. This enables highlighting of the principal subject and taking the foreground or background out of focus.