Thanks for the reply SW. When it comes to ettl-II I have the 550ex and naturally think that i will buy the 580 now. Can i still use the 550 as per normal ( but for the advantage the 580 gives with regards to distance and AWB adjustments ). Do you recommend i dive in for the 580EX
E-TTL II is in the camera; all the EX flashes will allow you to get E-TTL II on a compliant body. What the 430EX/580EX offer that earlier flashes don't are zoom adjusted for sensor size on compliant cameras (not a problem with FF; that was the previous default) and colour temp. reporting to compliant cameras.
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