Bizarre MkII & T-con anomoly? Any Ideas?

[CyberDyneSystems]

Recently I had occasion to desire the use of my Sigma 1.4X T-con in conjunction with the 1D MkII and a Sigma 500mm f/4.5 EX HSM lens.


This is a combination I am sure I have used succesfully in the past... the resulting max aperture is f/6.3 well within the f/8 required for the MkII to focus.

However..

The Combo WOULD NOT autofocus?

I disabled CF#17.. selected only the center AF point and tried both AI and Single.. still no AF.

Anyone have any Ideas?
Do I have some odd CF setting or has something "gone bad" (what on earth can go bad,.. both camera and lens function fine.. this hiccup only occurs with the 1.4x in line)

This used to work.. and i used it often on a 1D as well...

Thanks.

[eric1]

maybe the tcon isn't totally compatable with Canon's newest chip(MKII). just a thought. :?

[scottbergerphoto]

The Sigma 500 f/4.5 EX APO HSM works fine with the Canon 1.4X TC on the Mark II. I suggest you try the TC with a lens that normally works with it on a non series 1 camera and see if it works on a 10D or Rebel.
Regards,
Scott

[CyberDyneSystems]

Ahhh.. I forgot to give full disclosure..

I have used the Sigma 1.4X TC with the 100-400mmL IS.. (trid it again today in fact to be double sure) ...and that combo will AF on the MkII @ f/8 with the Sigma TC?

See.. it just keeps getting weirder?

Something very odd going on... :(

[Scottes]

CDS, I'll have my Canon 1.4 TC with me tomorrow. We'll see what happens.

[defordphoto]

CDS, I'll have my Canon 1.4 TC with me tomorrow. We'll see what happens.

Does the Canon TC mate with Sigma glass?

Part of this issue is why I have what I have in my sig....

[Scottes]

CDS, I'll have my Canon 1.4 TC with me tomorrow. We'll see what happens.

Does the Canon TC mate with Sigma glass?

Hmm. Dunno. But we'll see what happens.

[defordphoto]

CDS, I'll have my Canon 1.4 TC with me tomorrow. We'll see what happens.

Does the Canon TC mate with Sigma glass?

Hmm. Dunno. But we'll see what happens.

Film (?!?!) at 11.

[scottbergerphoto]

CDS, I'll have my Canon 1.4 TC with me tomorrow. We'll see what happens.

Does the Canon TC mate with Sigma glass?

Hmm. Dunno. But we'll see what happens.

Film (?!?!) at 11.
If you read my post above, you'll see that I already answered that question :roll: . The Canon 1.4X works fine with the Sigma 500 f//4.5.
Regards,
Scott

[defordphoto]

CDS, I'll have my Canon 1.4 TC with me tomorrow. We'll see what happens.

Does the Canon TC mate with Sigma glass?

Hmm. Dunno. But we'll see what happens.

Film (?!?!) at 11.
If you read my post above, you'll see that I already answered that question :roll: . The Canon 1.4X works fine with the Sigma 500 f//4.5.
Regards,
Scott

As you said, "See.. it just keeps getting weirder?"

Yes it does...

[CyberDyneSystems]

O-kay.. too make matters weirder..

Today I tried Scottes Canon 1.4X T-Con on the combo...

No joy.

So it is not an issue with my Sigma 1.4X t-con...

Which leaves the 500mm f/4.5... or My particular 1DMkII.

ScottBerger has the exact same lens,. the exact same Camera,. and the exact same 1.4X t-con as the one I tried today..

And it AF's for him.

Mind you... I have images taken with the same 500mm f/4.5 and Sigma 1.4X t-con that I took with a 1D "Classic" ... it autofocused there as well...

So.. this leads me to belive the particular incompatibility is stemming from my new MkII body?

Weirder and weirder.

Next stop?

The "Tape Trick" (which of course I should not need to try)