Why Does the Canon Flash Blink?
- Both Canon external flash units and smaller built-in flashes on Canon cameras offer red-eye reduction features. When activated, the flash sends out pulses of incandescent light for approximately 1.5 seconds. During this time the subject's pupils constrict, creating less surface area to reflect red blood vessels and cause red-eye in the photos. To eliminate these pulses of light, don't use the red-eye reduction mode.
- When using a Canon single-lens reflex camera with an external mounted Canon flash, expect the red light on the front of the flash to blink during automatic exposures. Setting the flash to TTL, A-TTL or E-TTL -- all automatic modes -- signals the flash to send out an infrared beam to estimate the distance between the subject and the flash. This measurement enables the camera to emit the right amount of light during an automatic exposure. Using the flash on manual mode disables the blinking red beam.
- If you experiment with the creative exposure settings on high-end Canon external flash units, try the multiple-exposure mode. The Canon flash will emit a series of light bursts, each one recording information on the camera sensor or one section of film. For example, the image of a golfer's swing showing the position of the golf club several times throughout the swing is created using multiple-exposure flash mode. Each burst records one position of the club.
- If you're photographing small children or pets with a short attention span, get creative. Explain to the subjects to keep smiling until the final big burst goes off. Tell children to practice their smiles during the small flashes so they're ready for the final burst. Since red-eye reduction doesn't work on pets, turn off this feature and use a manual exposure mode. Or, take the pet outside and use natural light to expose the picture.
