« on: January 07, 2013, 08:43:44 AM »
I received the 2x III for Christmas from my wife. My reasoning for wanting the extender was pretty much the same. I was looking to get to 400mm at a reasonable cost. Well, I was disappointed that my combination severely front focuses. I spoke to Canon CPS and they were happy to take a look, but since it's new, I returned it to Norman Camera. I was somewhat disappointed at their initial response. They will do their own test and let me know if they experience the same results. If they do, it will be replaced. If not, I will get a refund. I considered trying the micro-adjustment focus settings, but to me, it was so far off I didn't think that would take care of it.
Not sure if this helps, but it is my personal experience. I’m hoping that Norman finds an obvious issue and replaces it.