You can take three flash shot while automatically changing the flash output for each shot up to +/-3 stops in 1/3-stop increments (1/ 2 -stop increments if the camera enables only 1/ 2 -stop increments). This is called FEB (Flash Exposure Bracketing)
Flash Ratio with E-TTL II With on sender unit and on receiver unit or two receiver groups, you can set the flash ratio for E-TTL II autoflash shooting The example below has two receiver units and the sender unit disabled from firing.
In the same way as normal exposure compensation, you can set the exposure compensation for the flash. The flash compensation amount can be set up to +/-3 stops in 1/3-stop increments. (If the camera's exposure compensation is in 1/ 2 -stop increments, flash exposure compensation will be in 1/ 2 -stop increments as well)
QUICK FLASH Quick flash enables a flash to be fired before flash-ready, when the pilot lamp is still green Although the Guide Number (Gn) will be 1/6 to 1/ 2 that of the full output, Quick Flash is effective for nearby subjects and when you want a shorter recycle time
button again, the second-curtain sync icon will disappear. With E-TTL II / E-TTL, two flashes will be fired even at slow shutter speeds Stroboscopic flash cannot be set
