1.4x extender with 500mm on the 10D/20D

[EugeneK]

I am currently using a D60 and need a second body and am trying to decide on the 10D/20D. The 1.4x extender when used on my 500mm 4.5L does not allow AF on the D60. Does it work on the 10D? How about on the 20D based on the pre-reviews.
I do bird/butterfly photography and would love AF on this combination. :D

Thanks

[Scottes]

Alas, it won't work with any of those because the combo would put the max aperture smaller than f/5.6. You can tape the contacts (not recommended) or get a MkII - though I think CDS here had problems even with that.

[EugeneK]

Too bad. :( How about the high end cameras like the 1d Mk II. Will they autofocus?
-Eugene

[defordphoto]

Removed by RFMSports

[CyberDyneSystems]

--supposedly --

Mine stopped autofocusing with the 1.4X recently and I can't figure out why?

I've tried all the settings.. center AF only turning off expansion.. still no joy.

I don't know if it's a hardware problem, lens, camera, (NOT TC we tried two) or if it's my CF# setup.

I suppose I should try restoring factory settings...

[EugeneK]

Well maybe I'll get a 20D and see if I can find someone who will swap with me. :lol:

[defordphoto]

Removed by RFMSports

[CyberDyneSystems]

Oops..

Forgot to mention I am talking about the Sigma 500mm f/4.5 which is of course.. pertinant!

With the Canon 100-400mm for instance.. My MkII still AF's with the 1.4X T-con.. so in fact we can rule out my settings..

I guess the MkII and the Sigma just don't seem to want to get along this way anyomer :(

ScottBerger has the Same Lens and Camera and he gets AF with the 1.4X T-con.. (as did I for a while)

Ahh well.. probably a "Sigma thing"