Canon 1.4Tc on a 500mm L F.4

[Baron]

When i put my 1.4Tc extender on my 500mm lense it blocks the camera (5D II) to F8 and will not focus like a 2.0TC would do. Does any one have the same problem?

[bhowdy]

I use a Kenko Pro 300 1.4 that I use on my 500mm f/4 (Canon 1D MarkIII body)
It works great, the auto focus stays very quick. The f stop does adjust to f/5.6

I know that is not the exact answer to your question, since I am not using the Canon 1.4. For what it is worth though