The glass stand on the upper left is the smoking gun, the second has to be the zeiss. That is pretty impressive for the kit lens, but thats at f/8 without an out of dof transition visible. Wide open and looking throughout the dof transition, the difference would be glaring. Theres also the distinct color of the book, and the wood grain and background. Was this 100% crop then UPsized to 800? Looks like that or some added jpeg compression pp.