40D Center Point AF & Teleconverters?

[Steve Wheeler]

I’d read recently on another forum a post that said the 40D (or at least this individuals 40D) will not AF using the center AF point if a teleconverter was attached.

I just received my 40D yesterday and the plan going forward was to get the 500 f4 and a 1.4 TC sometime prior to November when I hope to make it out to Bosque again.
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NOT being able to use the AF center point with that combination would cause some major problems.

Canons own lens chart seems to indicate… If I’m reading it correctly… that there should not be any problems. I called Canon yesterday and the guy I talked to, while not an expert on the subject, said it should work fine.

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I posed the question on the forum mentioned above and out the 25 responses thus far it appears that it works for some, but not for others.

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It SHOULDN”T be a problem at all… Right?

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Does anyone here have a problem with not being able to use the center focus point to AF with a TC attached?

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If so is it something that can be fixed if sent back to Canon?

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Steve

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PS
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I rented a 600 f4 & 1.4 TC for use with my 30D just this last weekend. I had no problems at all.. In fact I was impressed how quickly it did AF using the center focus point.

[James Prudente]

I have 2 40D bodies and both function perfectly with either the 1.4 or 2.0 on the 500 f4 L IS USM lens with any and all AF point configurations. Try your 40D on a friends TC and 500 combo and if it has a problem take it back or send it to Canon right away.

Cheers,

Jim

[Steve Wheeler]

Thanks James! I plan to do just that as I have a friend here with both.

Very interesting... So you can even use a 2x with the 500 f4 and 40D? My understanding was AF wouldn't work on the 40D with anything slower than an f5.6?

Steve

[Jim Neiger]

Steve,

I have used someone elses 40D with a 50-0mm + 1.4xTC and it worksed just fine with the center AF point only. I also thought that it would not focus with a 2.0XTC unless the ppins were taped. I haven't tried it though.

[Steve Wheeler]

Yea Jim... I understood the pro bodies would AF to f8 and the "Pro-sumer" bodies (30D & 40D) to f5.6. Minus the pin-taping thing of course, which I've read works to 'some degree', but is so slow as to not be worth doing at all... At least according to some peoples expierences. (I've never tried it.)

This "Apparently" isn't as cut and dried as I thought however... At least based on the feedback from James above and on the other forum (DPReview) I posted the question on where the responses and expierences seemed to be all over the map. Very confusing... I would've thought it was either "A" or "B"... On or off... work or doesn't work.

Despite all that it is very reasuring to hear HERE that I won't have any problems with my plan... Other than comming up with $5k+ for a 500 & TC of course!

Steve

[James Prudente]

My mistake folks. My 40Ds both work with the 1.4 on the 500 f4 and both the 1.4 and 2.0 on the 300 f2.8. It is the pits to get old and have brain cramps.

Jim

[Steve Wheeler]

Quite alright James... I'm STILL happy to hear another thumbs up for the 40D/500/1.4x combo.

Steve

[Jim Neiger]

Steve,

I wouldn't completely write off using a 2x with the pins taped. IF it will Af that way, it will be slow, but still very usable. With the proper technique you can even make nice flight images with the very slow AF.

[Don Blue]

I can tell you 100% that the 40D af works very well with the 500 f/4 + 1.4...as thats the combo I'm shooting with. I just bought the 500 f/4 about a month ago. As far as taping the pins and trying to use a 2x it does not work well enough to be useful on the 40D.
I also have a 400 5.6 and I have tried taping the pins to use the 1.4 with it on the 40D and it's useless.

[Steve Canuel]

Steve,
Even my 20D works center point focus with the 500 + 1.4xTC. My coyote pics in the wildlife forum were both taken with that combo.

Steve

[IvoZafirov]

Just to share my experience from last weekend. I have 40D body and 400/5,6. Yestarday was the first time I tried adding 1,4x TC with tapped pins. It used to work with 30D fine with very little change in quality. Yestarday I discovered that 40D+400/5,6+1,4TC with tapped pins work just fine and the quality is much better than 30D body. This was a good discovery for me as when I bought 40D body I was told that with 400/5,6 +1,4TC the center AF point will not work.;)

[Steve Wheeler]

Thank you all for your responses!

I called Canon again and spoke to someone who at least SOUNDED like they knew what they were talking about this time. Canon's lens chart, thier rep and all of you are all saying everything is fine Steve... Chill.... The center focus point on the 40D works fine with a TC.

So I'm chillin'...

Thank you again!

Steve