https://www.youtube.com/watch?v=Fq4eruHwFno May 13 BIG BANG! First of all, I am now 100% certain that the Sony A7rVI and the 100–400mm f/4.5 GM lens will be announced on May 13 at 3 PM London time. I will be live blogging here and on my YouTube channel (subscribe), and I kindly invite you to preord…