Hi all,
I am expecting delivery of a new 70D tomorrow and have a question regarding the 2 stage MFA. I currently have a 7D so am aware of the principles of MFA however the 70D having the ability to MFA at 2 different focal points has me wondering.
I have the Tamron 150-600mm and what I want to know is can I MFA it to say 400mm and then again at 600mm? Or does it have to be the shortest focal length ie 150mm?
I use the lens almost always in the 400mm + range.
Many thanks.

