MattLivesey.Hertfordshire
Active member
Could anyone tell me which Canon camera bodies retain autofocus (without taping the pins) with a canon 1.4 teleconverter?
Doesn't make a difference whether it's a Mk 1,2 or 3 TC it's the aperture that counts.
Only the 1D series and the 5DMk3 will AF at f8 .The other bodies will AF at f6.3 maximum .( Just read the post above that says other bodies only AF to f5.6, this needs checking out so I might be wrong!)
It then depends which body and lens and TC combination you use to achieve AF.
An f2.8 lens with a 2.0x TC = f5.6.... no problems
An f4 lens with a 2.0x= F8 limited options dependant on which body you use.
An f4 with a 1.4 TC = f5.6 no problems
An f5.6 with a 1.4 lens =F6.3 no problems
An f5.6 lens with a 2.0x= f11 No way !
Dave
A 7D will not AF with say a 400mm 5.6 lens and a 1.4 converter.
John
The AF on most of them (excluding the 1D series and the 5D3) will only work with apertures of f5.6 or faster. Some third party lenses are f6.3 at the long end but tell the camera that they are f5.6 so as to retain AF. On your list there is one that is wrong, an f5.6 lens with a 1.4x will give f8 so will not AF with the non pro bodies.
Thanks John.
I have never owned a Canon body other than the 1D series and more recently, I purchased a 5D3. Neither the 1Dx or the 5D3 would AF at f8 when they first came out, and you had to download a fix to do so, which all goes to show that other bodies have the capability if only Canon would allow them to do so.
Nikon on the other hand don't do that.When I had a D300 ( Canon's 7D "equivalent" as we know) AF at f8 wasn't a problem.
A good reason to choose Nikon. If the 7D2 does come out it will be interesting to see what restrictions are put on AF capabilities.
cheers Dave
F5.6 plus 1.4 = 6.3 doesn't it ? But your right it seems as to Canon lenses not being able to AF, interesting that non Canon ones will.
See my comments above about Canon vs Nikon. All strange marketing to me, but the experts must have their reasons and markets defined.
cheers
Dave
A 1.4x will cost you one stop so an f5.6 becomes f8 (f6.3 is only 1/3rd of a stop from f5.6).
Like you say it seems to be a marketing choice for Canon and Nikon and in reality what we all want is the fastest lenses with the best AF... Shame it comes at a price!
As already pointed out Dave a 1.4x tc will cost you a stop so f5.6 + 1 stop = f8.F5.6 plus 1.4 = 6.3 doesn't it ? But your right it seems as to Canon lenses not being able to AF, interesting that non Canon ones will.
See my comments above about Canon vs Nikon. All strange marketing to me, but the experts must have their reasons and markets defined.
cheers
Dave
Yes, I use the 400/5.6 + 1.4x tc on the 5D3 and it AF's very well.Didn't firmware update allow 5d3 center-point to af at f8?
Didn't firmware update allow 5d3 center-point to af at f8?
What I was trying to say (badly) John was NON 1D or 5D3 Cameras will not AF at f6.3. In other words only 1 series + the 5D3 will.Just checked and yes it does.
Roy your previous post seemed to indicate the 5Dmk3 will not AF at 6.3
John