I've only ever gone for one 2x TC, and that was on the old Olympus OM system. It gave horrendous CA and I've shunned them ever since (my current TC is a Zuiko Digital 1.4 that works fantastically well). This one however looks very good after reading the specs. Hard to tell from your examples - the first shot is obviously showing the effects of ISO 1600 and does look a little soft. Looks like it will work well at lower ISOs though and should be a useful addition to long telephoto work
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