| 摘要 |
<p>An electronic flash control has an IR filter swung over the photocell for normal flash exposures and a second filter, with partial IR blocking, used when the flash is used for fill-in exposures in daylight. The two filters enable accurate exposures to be taken over a wide range of illuminations, avoiding under-exposure due to i.r. light being reflected from, e.g. leaves in the shady area brightened by the flash unit. The filter position is selected automatically by the level of light intensity, with the position of the flash-gun monitored by a fail-safe interlock. This prevents flash exposure if the flash gun is not in the ready position.</p> |
