very satisfied with the performance of this ... very extender can brightness loss (1 diaph), used on a bright lens f 2.8 70/200 as this is a real pleasure .I am sure we made the good choice when a quality fabriquation, use and rendering .And then you must not ask too much even has an optical good, and I think performance would be lower with the delivery and doubler .for packing as usual, always on top !!
