Teleconverter pleasant surprise

[troutfisher]

Just bought a 5Dc and still finding my way around it.I also have a 40D and a 100/400 together with a kenko pro dg 1.4 TC.
The 100/400+TC will not AF on the 40D with the pins taped,it just hunts all over the place.
Imagine my surprise when I stuck the same combo on the 5D,it AF's as if the TC was not there,and not in particularly brilliant light,just snaps into focus ,IQ is not bad obviously a bit degraded.But I now seem to have a 560mm lens with AF.
It must be something to do with the FF sensor and/or pixel density any thoughts anyone?

Chris

 

[HoppyUK]

It's not the sensor or pixel density (the AF is unrelated) but it's a fact that some Canons respond to the pin taping trick, and others do not.

I had that exact same combo on a 40D and that wouldn't AF as you say, but it would on a 350D I've also heard that the 7D won't play, but other xxxD models will. I haven't got the 100-400L anymore, so can't try my 5D2.