An aperture unit includes a base plate, a cover, a plurality of aperture blades, a drive ring, and protrusions. The aperture blades are disposed between the base plate and the cover, and adjust the amount of light passing through by varying the size of an opening. The drive ring is disposed between the base plate and the cover, and is rotationally driven when the aperture blades are opened and closed. The protrusions are provided to the drive ring and the cover, respectively, and support the aperture blades in the direction of suppressing upward warpage of the aperture blades in a state in which the aperture blades move in the direction of reducing the size of the opening.

The present invention provides a board mountable system for filming underwater video. The inventive board mountable system can be mounted to the underside of water vehicles for incorporating a camera for filming from an underwater perspective. The inventive board mountable system is shaped to minimize drag as a result of the mounted camera or camera system. Embodiments of the inventive system includes a fin shaped housing for holding a camera or camera system. In certain embodiments, the fin is removably attached to the water vehicle, such as a surf board, where the fin housing can be swapped with other fins being used with the water vehicle for controlling the direction of a watersports board in motion. These embodiments of the inventive system further include a connection means for connecting the fin to the underside of a water vessel.

The present invention provides a board mountable system for filming underwater video. The inventive board mountable system can be mounted to the underside of water vehicles for incorporating a camera for filming from an underwater perspective. The inventive board mountable system is shaped to minimize drag as a result of the mounted camera or camera system. Embodiments of the inventive system includes a fin shaped housing for holding a camera or camera system. In certain embodiments, the fin is removably attached to the water vehicle, such as a surf board, where the fin housing can be swapped with other fins being used with the water vehicle for controlling the direction of a watersports board in motion. These embodiments of the inventive system further include a connection means for connecting the fin to the underside of a water vessel.

A method of film production includes the steps of obtaining defect information including information on the position of a defect (D) in a separator original sheet (12b), slitting the separator original sheet (12b) to produce a plurality of separators (12a), and determining, on the basis of the defect information on a single defect (D), that a separator (12a) actually having the defect (D) and another separator (12a) adjacent to the above separator (12a) are defective.

A method for film production includes the steps of obtaining information on the position of a defect (D) in a separator (12a) and providing marks (LA, LB) at the respective positions in the vicinity of the defect (D), the marks indicating the position of the defect.

A camera includes a counter rotatable about a support shaft, a spring that urges the counter in a first rotation direction, a rotary member and a drive cam that rotate the counter in a direction opposite to the first rotation direction, a stopper rotatable about the support shaft, and a spring that urges the stopper in a second rotation direction. The counter includes an outer circumferential surface that changes an indication in a circumferential direction, and a first engagement portion including a plurality of projections. The stopper includes contact tabs that receive a force acting in a direction opposite to the second rotation direction from at least one of a film pack or a door, and an engagement tab engageable with one of the projections on the first engagement portion on the counter to restrict rotation of the counter in the first rotation direction.

The present invention provides a board mountable system for filming underwater video. The inventive board mountable system can be mounted to the underside of water vehicles for incorporating a camera for filming from an underwater perspective. The inventive board mountable system is shaped to minimize drag as a result of the mounted camera or camera system. Embodiments of the inventive system includes a fin shaped housing for holding a camera or camera system. In certain embodiments, the fin is removably attached to the water vehicle, such as a surf board, where the fin housing can be swapped with other fins being used with the water vehicle for controlling the direction of a watersports board in motion. These embodiments of the inventive system further include a connection means for connecting the fin to the underside of a water vessel.