Thanks for that wippers.
The 70-200 f2.8 is listed on the compatability site I looked at, but the f4 version isn't.
Hence my confusion.
I suppose the mount is identical on both lenses though.
I have a Sigma 1.4 teleconverter.
I am shortly getting a Canon 70-200 f4L.
Will these work together. Would really like to hear from anyone who has used them as I don't want to damage my camera or lens.
Cheers.