Abstract

Rangefinders for cinema cameras may have limited accuracy. Herein, a rangefinder has a set of right lenses and a set of left lenses. A pair of lenses taken one from each side have nominally the same focal length. Different lens pairs have different focal lengths. The rangefinder includes an image detector for each lens. Electronic circuitry connected to the imagers automatically selects which of the pairs of lenses is to be used for range determination. The selection is the pair of lenses with the longest focal length and tightest field of view that can image a target subject in a scene that is being filmed. The selection changes automatically as the target subject moves closer to or away from the cinema camera. By using the longest focal length whenever possible, the overall accuracy of range determination is improved.

IPC Classes  ?

• G01C 3/02 - Measuring distances in line of sightOptical rangefinders Details
• G01C 3/14 - Measuring distances in line of sightOptical rangefinders using a parallactic triangle with variable angles and a base of fixed length in the observation station, e.g. in the instrument with binocular observation at a single point, e.g. stereoscopic type
• G03B 13/18 - Focusing aids

Abstract

When filming a scene, the focal distance of the video camera is often controlled remotely, and can be switched between manual and autofocus modes. To overcome sudden movements in the lens upon reverting to manual mode, and to avoid disrupting a user's grip on the manual control during autofocus, the traditional distance ring indicator is split into separate controller and indicator components. The controller permits manual input, while the indicator tracks the desired distance. In manual mode, the controller and indicator move in unison. In autofocus mode, the indicator tracks a rangefinder input but the controller is not moved. In a hybrid mode, the controller offsets the rangefinder input. In all cases, the position of the lens moves with the indicator.

IPC Classes  ?

• G03B 3/12 - Power-operated focusing adapted for remote control
• G03B 3/02 - Focusing arrangements of general interest for cameras, projectors or printers moving lens along baseboard
• G03B 17/18 - Signals indicating condition of a camera member or suitability of light
• H04N 23/67 - Focus control based on electronic image sensor signals

Abstract

When filming a scene, the focal distance of the video camera is often controlled remotely, and can be switched between manual and autofocus modes. To overcome sudden movements in the lens upon reverting to manual mode, and to avoid disrupting a user's grip on the manual control during autofocus, the traditional distance ring indicator is split into separate controller and indicator components. The controller permits manual input, while the indicator tracks the desired distance. In manual mode, the controller and indicator move in unison. In autofocus mode, the indicator tracks a rangefinder input but the controller is not moved. In a hybrid mode, the controller offsets the rangefinder input. In all cases, the position of the lens moves with the indicator.

IPC Classes  ?

• G03B 13/32 - Means for focusing
• H04N 5/232 - Devices for controlling television cameras, e.g. remote control