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Author Topic: 5D III with 2X extender on a 2.8 70 - 200 Lens  (Read 1683 times)

mStevens

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5D III with 2X extender on a 2.8 70 - 200 Lens
« on: September 01, 2012, 06:05:55 PM »
I cannot find the threads that discussed issues using an extender on a 5D III. It had something to do with aperture 8.0. Can someone refresh my memory on what that the issue was?
5D Mark III | 40D| 2.8L IS II 70-200| 2.8L 24-70| 1.8 EF 85| EF 2X II| 600 EX-RT

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5D III with 2X extender on a 2.8 70 - 200 Lens
« on: September 01, 2012, 06:05:55 PM »

neuroanatomist

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Re: 5D III with 2X extender on a 2.8 70 - 200 Lens
« Reply #1 on: September 01, 2012, 06:10:57 PM »
No worries for you. A max aperture of at least f/5.6 is needed for AF, and an f/2.8 lens with a 2x TC is f/5.6 (the aperture you set is irrelevant, AF is done wide open).  Do note that a 2x TC will slow down the AF by 75%, though.
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mStevens

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Re: 5D III with 2X extender on a 2.8 70 - 200 Lens
« Reply #2 on: September 01, 2012, 06:17:54 PM »
Thanks for the quick response. I am shooting pics of my daughter's soccer tournament game today and at the first game i did notice a lag in the focusing. I did not know about the reduction in the AF. I am going to her second game in a few moments and I think I will leave the extender in the hotel room. I kind of regret bringing my FF on this trip. I think next time I will use my crop frame camera.
5D Mark III | 40D| 2.8L IS II 70-200| 2.8L 24-70| 1.8 EF 85| EF 2X II| 600 EX-RT

canon rumors FORUM

Re: 5D III with 2X extender on a 2.8 70 - 200 Lens
« Reply #2 on: September 01, 2012, 06:17:54 PM »