canon 200mm 2.8L + 2x

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Jonathan
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Hi
Has anyone used this combination? Space at a premium for an upcoming trip, 400 f5.6 equivalent would be a decent and quite useful focal length. Would I be hugely disappointed with the output versus the 400mm prime?
Thanks in advance
Jonathan
 
I think Les mclean has used one with a 1.4x to very good effect if you want to do a search :)
 
I took some test shots last year for someone else asking the same question. It's very usable....not quite the quality of the 400/5.6 and definitely not comparable in focus speed.

Bob
 
Mate of mine uses the 200f2.8L Mk II with TCs (x1.4 and x2) to good effect.

Of note though the AF speed takes a big hit (as mentioned above) but more importantly the lens is a bit picky about which TCs it will AF with. The Canon ones (I believe) are ok but Kenko reporting and non-reporting TCs do not AF well at all with the Mk II version of this lens.
 
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I have used my 70-200 2.8L MkI with a x1.4 TC MkII and it works really well for me. I shot a rugby match yesterday with this combo without any problems. I would be interested to hear how the x2.0 TC performs.
 
Anyone had any experience of the Sigma 150-500 OS in comparison as I'm selling mine due to needing some cash, but in the future I'd like something with the similar reach again and had thought about this combo.

Also how badly is the AF speed hit and how good are the images?
 
Canon Bob said:
A 1.4x Extender reduces AF speed to 50% and a 2x to 25%

Bob
Click to expand...

In terms of light transmission, it is true that a 1.4x Extender costs you a stop of light, and a 2x 2 stops. However, I don't think it's correct that there is a direct linear relationship between AF speed and light transmission. Otherwise, our cameras would be ridiculously slow in low light, and that simply isn't the case. Heck, my camera was even AF'ing with a 10 stop ND filter just today, quite rapidly it has to be said.
 
Simes123 said:
....However, I don't think it's correct that there is a direct linear relationship between AF speed and light transmission. ......
Click to expand...

I didn't say that there was, I simply quoted Canon's own figures for AF speed degradation when using their Extenders.

Bob
 
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Hmn, I may have used the wrong terminology in my post, what I meant is do the extenders slow down the speed at which auto-focus locks on to a subject?

Interesting to note the f-stop reduction though.
 
JohnN said:
Hmn, I may have used the wrong terminology in my post, what I meant is do the extenders slow down the speed at which auto-focus locks on to a subject?

Interesting to note the f-stop reduction though.
Click to expand...
Your terminology was understood John....Yes, they slow down the AF and it's 50% for a 1.4x and 75% for a 2.0x

Bob
 
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Canon Bob said:
I didn't say that there was, I simply quoted Canon's own figures for AF speed degradation when using their Extenders.

Bob
Click to expand...

I've not seen Canon put a figure on it Bob - sorry; I just assumed you were linking the AF speed to the stop or 2 stop loss for the 1.4x and 2x convertor respectively. Looking here, http://cpn.canon-europe.com/content/education/infobank/lenses/extenders.do it would appear that AF speed may be affected but it doesn't ascribe a value to it, which is as I would expect.

Simon

P.S. From a quick google, although I couldn't find anything from Canon in this regard, there was lots of user reports suggesting that it is Canon lens/camera firmware that causes a slowdown for accuracy reasons.
 
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Simes123 said:
I've not seen Canon put a figure on it Bob - sorry; .......
Simon
Click to expand...

Simon,
No problem....here's Canon's quote
"As with previous EF Extenders, usage of Series III EF Extenders lowers AF drive speed to improve AF performance. When Extender EF 1.4X III is used, AF drive speed is reduced by 50%. When Extender EF 2X III is used, AF drive speed is reduced by 75%. This may seem like a drawback, but in reality subject tracking performance remains quite high when Series III Extenders are used with IS II lenses"
To be found here http://www.learn.usa.canon.com/resources/articles/2011/updates_supertelephoto_article.shtml (page 9 unless you view in single page mode)

Bob
 
Thanks Bob - interesting. Sounds like they are doing it for accuracy reasons. In practice, half of very fast, is still very fast :) I don't notice much of a slowdown with the 1.4x in practice at all.
 
Interesting, thanks for the specifics and also interesting to see its not noticeable in real world use, because those numbers did seam pretty steep.
 
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