E-TTL II Flash System
All current EOS digital SLRs incorporate the E-TTL II flash system for consistently accurate exposures. This advanced distance-linked flash algorithm works with the camera's internal flash or any EX series Speedlite flash unit. It monitors readings
from multiple metering zones, taking into account factors such as lens distance information from compatible EF lenses, reflective objects and ambient light in order to calculate flash output.
E-TTL II will reward you with accurate exposures in circumstances that can often confuse conventional metering systems – such as recomposed shots or scenes with reflective objects that could otherwise result in over- or underexposure.
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