Filter unit, filter selection method, and imaging device

A filter selection method, comprising:

• rotating a disk provided with a plurality of filters including a neutral density (ND) filter having a continuously variable transmittance, wherein
• the ND filter is a polarization filter,
• the polarization filter has a non-circular shape whose longitudinal direction is in a rotation direction of the disk, and
• the disk provided with the plurality of filters is provided between an imaging unit and an ultraviolet cut filter that blocks ultraviolet components contained in an incident light.

An imaging device, comprising:

• an imaging unit configured to capture an image of a subject;
• and
• a filter unit having a disk provided with a plurality of filters including a neutral density (ND) filter and having a continuously variable transmittance, wherein
• the ND filter is a polarization filter,
• the polarization filter has a non-circular shape whose longitudinal direction is in a rotation direction of the disk, and
• the filter unit is provided between the imaging unit and an ultraviolet cut filter that blocks ultraviolet components contained in an incident light.