RonFrank
Contributor
Larry C:Especially if they are on sand or other white background, or are highly reflective. I've blown out so many Lemon Dorids I can't count them all.
Actually white reflective objects should have the opposite problem, IOW's getting under exposed. The reflective and white nature of an object will result in the meter assuming there is more light on the subject than there is, and underexposure.
If you are getting white/reflective subjects blown out in Flash TTL mode, than there could be a few things going on. One maybe that the flash is just too close to the subject. Another maybe that the TTL mode can only control the flash over X number of stops, where manual mode may in fact include more.
Without knowing exactly what you are shooting, this is speculation on my part as to why white objects would be getting blown out in TTL. However the explaination of how the metering works is generally accurate.