摘要 |
An exposure control circuit associated with TTL automatic electronic flash includes a diaphragm control circuit. When the electronic flash is mounted on a TTL direct photometry camera capable of photometry of reflection from a film surface in order to take a picture with the aid of the electronic flash, the diaphragm control circuit assures the emission of light from the electronic flash in a reliable manner, by automatically establishing a diaphragm value between a given diaphragm value and a minimum diaphragm value, the established diaphragm value assuring a proper exposure with an exposure period which is closely synchronized with the operation of the electronic flash. |