Troubleshooting Guide

If a problem occurs with the transmitter, first refer to this troubleshooting guide. If this troubleshooting guide does not resolve the problem, contact your dealer or nearest Canon Service Center.

Normal shooting

The power does not turn on.

  • Insert the mounting foot in the camera's multi-function shoe until it clicks into place, then slide the mounting foot lock lever to the right to secure the unit to the camera ().
  • Clean the transmitter and camera contacts if they are dirty.

The power turns off by itself.

  • The transmitter's auto power off has been activated (). Either wake the camera or press the MENU button on the ST-E10.

The camera's battery life does not last long.

  • The ST-E10 consumes camera battery power even if the camera's power-saving or auto power off functions have been activated. Turn off the ST-E10 when possible if you are not using it.

Receiver units do not fire.

  • Make sure receiver units support wireless flash photography using radio transmission.
  • Set the transmission channels and wireless radio IDs of the sender unit and receiver units to the same number ().
  • Make sure receiver units are within transmission range of the sender unit ().

Receiver units sometimes fail to fire or unexpectedly fire at full output.

  • Position the receiver units at a location with the clearest possible view of the sender unit.
  • Make sure receivers are facing the sender unit.

Pictures are under or overexposed.

  • If the main subject looks very dark or very bright, set flash exposure compensation ().
  • If there is a highly reflective object in the picture, use FE lock ().
  • With high-speed sync, the faster the shutter speed, the lower the guide number. Move closer to the subject ().
  • When using autoflash with three firing groups (A, B, and C), do not fire with firing group C pointing toward the main subject ().
  • When shooting with each firing group set to its own flash mode, do not fire multiple firing groups set to [AutoExtFlash] or [E-TTL II] when they are pointing toward the main subject ().

The picture is very blurred.

  • Shooting with the shooting mode set to Aperture-priority AE Aperture-priority AE or Program AE Program AE mode under low light activates slow-sync shooting, which results in slower shutter speeds. Either use a tripod or set the flash sync speed in [Slow synchro] ().