TTL AV, TV AND M MODES
When this flash unit is used with your camera set to AV, TV or M modes, the flash exposure will be automatically controlled by the camera based on the combination of shutter speed and aperture value.
*For TV mode, do not exceed the camera’s maximum flash synchronization speed. In AV mode, setting at a slow speed will usually result in blurry pictures caused by the shaking of one’s hand. In such situations, the use of tripod is recommended.