Troubleshooting
Why is my photo not properly exposed?
Consult the owner’s manuals for your flash and camera to understand how exposure decisions are made. While the ControlTL system can greatly expand the operating range of Canon’s E-TTL II system, and over- come inherent problems with an optical communication system, it does nothing with exposure decisions made by the camera. Make certain your shooting situation allows enough direct or reflected pre-flash to be visible to the camera.
If you have more than one remote E-TTL II flash (either in basic E-TTL II mode or on one Canon group/zone when using ratios) then it is one “piece of light.” If the camera can measure the output from one flash, but does not see the other, it will make a calculation based on the light it sees. Both flashes will get sent the same value from the camera and both flashes will trigger at that same value. This may not yield the results you want. You may need to reposition the flashes to ensure the camera yields a proper exposure.
Why didn’t my remote flash trigger in the exposure?
Watch the remote flash as you trigger. If you see the small pre-flash happen, but not a 2nd flash, then the camera decided not to use that flash in the exposure. The camera did not see enough of the pre-flash to make a flash exposure calculation. The radios and flash are working properly. Reposition the flash or subject so that the reflected light will be more visible to the camera, or add another flash to provide more pre-flash light for the camera to measure. If you are using a light modifier on the remote flash, try adjust- ing it to allow more light or consider removing it. Other questions to consider in your shooting scenario:
•Is the ambient light brighter than the pre-flash from the camera’s perspective?
•Is the pre-flash to subject distance too great or at too great an angle relative to the camera?
•Is the subject too small (not enough reflected pre-flash reaching the camera) for the metering mode selected in the camera?
