Control circuit and method for controlling the operation of a camera having a B shutter operating mode

A method for controlling operation of a camera having a release switch and a shutter, comprising the steps of:

• selecting a bulb shutter operating mode of the camera;
• measuring the ambient light of a scene to be photographed by the camera in the bulb shutter operating mode;
• computing a film exposure time period, based on the measured ambient light of the scene;
• displaying the exposure time period;
• detecting a user input when a user compensates the film exposure time period;
• compensating the exposure time period in accordance with the user input when detected;
• displaying the exposure time period when compensated;
• generating a start signal to begin the exposure time period when the release switch is operated and an end signal at the expiration of the exposure time period without the operation of the release switch;
• opening the shutter in response to the start signal;
• and
• closing the shutter in response to the end signal.

A control circuit for a camera, comprising, in combination:

• a mode selector operable by a user to select a bulb shutter operating mode of the camera;
• an exposure time selector operable by the user to select an exposure time period;
• a microcontroller for registering the exposure time period selected by the user, the microcontroller generating a start signal to begin the registered exposure time period, timing the registered exposure time period, and generating an end signal upon expiration of the registered exposure time period;
• a display connected to the microcontroller for displaying the registered exposure time period to the user;
• and
• an actuator connected to the microcontroller for opening a camera shutter automatically in response to the start signal, retaining the camera shutter open during the registered exposure time period and closing the camera shutter automatically in response to the end signal.