The Tiffen Variable ND filter is a versatile tool that offers the ability to use multiple neutral density filters in one device. It is mainly used for controlling depth of field and exposure in photography, but is also popular in videography due to its convenience and compact size.

The Tiffen Variable ND filter works on the same principle as a circular polarizer. You simply rotate the filter until you achieve the desired effect. It provides continuous control of the amount of light passing through the lens, with a range approximately from 2 (ND 0.6) to 8 (ND 2.4) stops, while maintaining the integrity of the image.