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Canon 1.4x ii or 1.4x iii?? (1 Viewer)


Well-known member
United Kingdom
Hi guys, I’ve just bought canon 100-400 mk ii & was going to try it with extender on my 7d mk ii, but does it matter which 1.4x & will the Mark ii extender still AF on my 7d mk ii or is it just the mk iii which works..


Roy C

Occasional bird snapper
I have tried both with my 100-400 MkII and cannot see any difference whatsoever (in both IQ or focus speed). When it comes to 2x tc then the MkIII converter is certainly best. The MkIII converters were primarily designed for the latest versions of the big white primes and not the likes of the 100-400 MkII.
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