MattLivesey.Hertfordshire
Active member
Could anyone tell me which Canon camera bodies retain autofocus (without taping the pins) with a canon 1.4 teleconverter?
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Cameras that Retain Autofocus with Teleconverters (1 Viewer)
- Thread starter MattLivesey.Hertfordshire
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MattLivesey.Hertfordshire
Active member
Thank you! That page has really helped me. Will the compatibility vary with the version of the teleconverter? So will a 1.4 x and 1.4 x II have the same compatibility with the lenses as a 1.4 x III (the one show in the chart) ?
john miller
Well-known member
Put simply most canon cameras up to the 7D will autofocus up to f5.6, ie a f4 lens with a 1.4 converter or a 2.8 lens with a 2X.
The 5D and 1D series will autofocus up to f8. ie a 5.6 lens with a 1.4 or a f4 lens with a 2X
John
www.kellingnature.zenfolio.com
The 5D and 1D series will autofocus up to f8. ie a 5.6 lens with a 1.4 or a f4 lens with a 2X
John
www.kellingnature.zenfolio.com
Dave Williams
Well-known member
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 !
Adding a TC will slow down AF, the bigger the aperture the less it's noticeable but you are pushing it the smaller it gets.
Also, the smaller the aperture the less focal points that are available for the camera body to use. Even with the 1DX the camera can only use a maximum of 5 of it's focus points , all clustered in the middle of the frame, instead of the potential 61 that it has with some other lenses.This not only makes AF slower but also makes framing the subject more difficult especially if you are hand holding a heavy lens.
No matter which body you have though, focus is achievable manually if you have a focus ring on the lens. Depends how good your eye sight is , mine's dodgy !
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 !
Adding a TC will slow down AF, the bigger the aperture the less it's noticeable but you are pushing it the smaller it gets.
Also, the smaller the aperture the less focal points that are available for the camera body to use. Even with the 1DX the camera can only use a maximum of 5 of it's focus points , all clustered in the middle of the frame, instead of the potential 61 that it has with some other lenses.This not only makes AF slower but also makes framing the subject more difficult especially if you are hand holding a heavy lens.
No matter which body you have though, focus is achievable manually if you have a focus ring on the lens. Depends how good your eye sight is , mine's dodgy !
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john miller
Well-known member
Dave
A 7D will not AF with say a 400mm 5.6 lens and a 1.4 converter.
John
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.
Dave Williams
Well-known member
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
Dave Williams
Well-known member
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
I wouldn't assume that other bodies can do this just because those two could, they do have the best AF system to be found in any Canon DSLR. I suspect that without the restrictions the AF would at least attempt to work but would no doubt be sluggish and possibly less accurate. As I understand it Canon limited the AF in this way as they did not feel that AF was upto standard when shooting at f8 and slower. One way round this with modern bodies is to use liveview focusing as this uses a different system for AF and will happily AF at f8 (although it is much slower that standard AF).
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!
Dave Williams
Well-known member
Thanks, hopefully there are some interesting bits of information for all concerned in this post !
The point I made about limited focus points has a huge bering on AF speed as well as composition I imagine.
Roy C
Occasional bird snapper
As already pointed out Dave a 1.4x tc will cost you a stop so f5.6 + 1 stop = f8.
BTW the non 1series/5D3 cameras will not AF at f6.3, the only reason they appear to do so with certain third party lenses is because the manufactures fool the AF system into thinking it is f5.6!
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Roy C
Occasional bird snapper
Yes, I use the 400/5.6 + 1.4x tc on the 5D3 and it AF's very well.
john miller
Well-known member
Just checked and yes it does.
Roy your previous post seemed to indicate the 5Dmk3 will not AF at 6.3
John
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Roy C
Occasional bird snapper
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.
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the black fox
Well-known member
There's no way round it on either canon or nikon unless you are able to spend upwards of 3k on a lens ,the big whites of canon and the heavy large blacks of nikon hold there price for a reason ,I use a 400 f5.6 plus 1.4 tc on a 1d body it's fine but it's always a compromise .
I have actually been mulling over going back to a nikon d7000 and tamron 150-600 to get the reach and DR,but then remember the niggles I had previously and missed shots which I don't get with canon ,also the thought of a f6.3lens in the winter puts me off .
I have actually been mulling over going back to a nikon d7000 and tamron 150-600 to get the reach and DR,but then remember the niggles I had previously and missed shots which I don't get with canon ,also the thought of a f6.3lens in the winter puts me off .
