# Which telephoto lens has the fastest AF



## brendan (Dec 13, 2011)

Im shooting very fast paced sports and was wondering which telephoto lens would be best?


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## branden (Dec 13, 2011)

Your name seems familiar...


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## B-Man (Dec 13, 2011)

i think in order to have a fast AF, you need a decent camera body? no? yes?


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## Mt Spokane Photography (Dec 13, 2011)

Canon does not spec AF speeds, so you may get opinions from users about their favorite lens.

However, the 400mm f/2.8 is THE popular lens for professional photographers at sporting events, so its certainly in the very top echelon.

If you are looking for budget priced lenses, it depends on the focal length and price range. The 70-200mm f/2.8L is excellent, my 85mm f/2.8 is very fast for a low cost. My 135mm L is also reasonably fast focusing.

Not all of the "L" lenses are fact focusing, my 100-400mm L is not super fast, for example, while the 400mm f/5.6 L is reasonably fast for a under $1500 lens. The 85mm L, is noted for being slow to focus, but its not intended for sports, and is fast enough for portraits.


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## bigblue1ca (Dec 13, 2011)

I concur about the 70-200 2.8, the first thing I noticed when I bought it was it's focus speed in AI Servo.


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## jcns (Dec 13, 2011)

If your needs require a certain range, you are sort of stuck. 
if you need 400mm, but the 300mm has faster AF. are you going to get the 300mm and slap on an extender/tc?


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## Viggo (Dec 13, 2011)

NO doubt .. the new 300 L II will be blistering. I owned the old one and only beaten by the sick new 70-200, and I KNOW that Canon won't let a budget lens like that get the upperhand, the new 300 combined with a mk4 or X will be the worlds fastes AND most accurate...


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## pj1974 (Dec 13, 2011)

I currently own a number of Canon USM lenses (15-85mm, 70-300mm L, 100-300mm, 100mm macro non L). I also own a few non-USM Canons (18-55mm, 50mm f1.8) and the Sigma 10-20mm EX HSM. 

In my experience, the fastest focussing of the lenses I own is the Canon 70-300mm L, though all the other Canon USMs are very close behind it in terms of focussing speed. The Sigma HSM is also fast, but just a bit slower than the Canon USMs imho.

Perhaps in practice I 'feel' that the 15-85mm as my current 'walk around' is a bit faster than the 28-135mm USM which I used to own till a few weeks ago. I've never tested that scientifically, and the difference would be small. I know that my Canon 100-300mm (while not so great optically wide open, particularly not at 300mm) - was able to capture some sports photos due to its focussing speed that other non-USM lenses I had tried couldn't. 

I wonder if there are more aspects that come into play to actually answer the question (eg some lenses might focus quicker between smaller focus differences (eg between 10m and infinity focus) - whereas be slower from the 'macro' (MFD) to 10m range.

The theory that a prime lens should be able to focus quicker (because of the less complicated design compared to a zoom) might be true. A quick note - when I want very quick focussing (eg when I take some photos of motorsports, I nearly always switch my IS off, and I wonder if that gives me slightly quicker focus speed too.., though sometimes I have IS on - eg mode 2 for panning).

Also, I think it depends on the amount of available light. My understanding is that if there is low light (or low contrast) a lens at least f2.8 or faster will gain the focussing precision of many Canon DSLR sensor's "extra precision f2.8 cross focus point" (in the centre AF point). I've heard many people say that their 85mm f1.8 is very good at quick focus for eg indoor sports (where I could imagine eg a Canon USM lens which has f5.6 might struggle, or at least 'focus slower'.

Finally, another point while on this topic. My Canon 100mm macro (non-L) focussed quickly and accurately, also at 'non focus distances'. I often use it for portraits and subject isolation (and can use the handy focus limiter so it doesn't search / hunt near the macro range). However some people have complained about their Canon 100mm USM nonL's "slow focus speed". I've read in a few places that the later batches of some Canon 100mm USM nonLs focussed quicker. (and yes, I am aware there is a non USM Canon 100mm macro too... I'm not including that in this discussion).

For my use, my 70-300mm L does everything I want it to do, including fast focus. I mainly use it for wildlife (including birds in flight), and occasionally other moving subjects (eg motorsports, or casual sports or children camps). So I realise that's not quite as demanding as some other applications.

Hope my post is useful, even though I'm conscious I am raising some new variables into the equation! 

Kind regards

Paul


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## AprilForever (Dec 13, 2011)

My 300 2.8 is MUCH faster than my 70-200 2.8... which is MUCH faster than my 70-300 IS (non L) was... which was MUCH faster than my 75-300 was... which was MUCH faster than my my Quantaray 70-300...


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## briansquibb (Dec 14, 2011)

I am very impressed just how quick the 400 f/2.8 IS is to AF on the 1D4.


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## brendan (Dec 14, 2011)

Thanks everybody all of this really helped! and if any of you wanted to know i went with the 300mm 2.8!


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## Edwin Herdman (Dec 15, 2011)

AprilForever said:


> My 300 2.8 is MUCH faster than my 70-200 2.8...


I suspect part of the reason for this is that you can (or must) stay farther away from the subject, so the lens elements have less distance to travel (i.e. compare this to a wide angle lens which might have to travel through most of its distance). I recall reading a discussion about this point before.

@ brendan: Hope you like the new lens and get some great pictures out of it!


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## Fab_Angilletta (Dec 15, 2011)

judging by the prices and aimed market : 300 f/2.8 II and 400 f/2.8 II *should* have the fastest AF


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## niccyboy (Dec 16, 2011)

would love a comparison of this with bodies/lens combos. would be interesting..


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## pwp (Dec 16, 2011)

AprilForever said:


> My 300 2.8 is MUCH faster than my 70-200 2.8...



My experience with these two lenses backs this 100%. With the 300 f/2.8 on my 1DIV body the AF keeps up right up to minimum focus distance provided your chosen AF point stays locked where you intended. 

But Brendan, for anyone here to give you relevant responses, we need to know what sort of sports you shoot. With just about any lens a 1DIV will track faster and more accurately than a 7D, 60D 5DII etc. It's designed and built for high performance and this is what you pay for.

The 400 f/2.8 is a supreme favourite with sports shooters, and will most likely become more so with the release of the 1DX and the subsequent loss of the 1D series APS-H 1.3X sensors. 300mm on the 1DIV gives us 390mm with the 1.3X.

You may want to do a bit of research on the apparently brilliant new Sigma 120-300 f/2.8 OS. 

King of _fast _AF is probably the legendary 200 f/2L. There is a virtual black market for this lens now. Wish I had the foresight to drop the Visa card on one while they were still a current listed lens.

Paul Wright


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## Viggo (Dec 16, 2011)

Just to clearify, when I said the 70-200 was faster than my 300 2,8 IS, I meant the mkII 70-200, and that isn't up for discussion. The new AF Canon is putting out in the new lenses is from another world. Now it doesn't rotate to the desired distance, it JUMPS there! It feels almost on and off rather than fooocuuusiing. The new 70-200 is Canon's greatest lens to date. To have a zoom with that low weight, short mfd at 2,8 and match nearly all primes for sharpness is just crazy. I never use it though, but I'm keeping it until I see if it will be put to better use on the FF 1d X, on crop it's just ,neh...


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