Canon 2x II Extender EF - Autofocus On 100-400L

[canonloader]

Is that true? On this lens, the autofocus doesn't work? Does anyone have experience with this combination? I've been thinking of getting it. TIA. :)

[Woolburr]

It is true...with a 2x TC the lens becomes f/11 at 800mm. F/8 will autofocus on a 1 series body, f/5.6 for other bodies... so with a 2x TC...there is no autofocus for the 100-400.

[crn3371]

As far as I know, only a 1 series body will auto focus above f5.6 . I've heard that with a 1.4x converter on a 30D that auto might work, but with a lot of hunting.

[Billginthekeys]

it will focus with a 1.4x on 1series bodies only. and it wont autofocus on anything with the 2x. the results are less than stellar aswell.

[canonloader]

OK, thanks guys.

[akhater]

out of experience, with a 30D if you are using the "cheap" converters (the ones that doesn't transmit f stops to the camera) the camera will still TRY to AF. with a 1.4x autofocus will still work and it is quite usable in good light, in low light it will haunt. 2.0x autofocus is almost impossible.
100-400 FAQ (http://www.adidap.com/2006/09/25/faq-canon-ef-100-400-l-is/)