Quality of x1.4 or x2 convertors on Canon 100-400 IS L ?

Yes I knew about the autofocus not working. AAMOF, I posted something about that earlier in the thread. What I was asking about was the confirmation light when using the 1.4 extender with the 100-400. I don't get any confirmation light at all. Not even a beep when the extender is on. So I was asking if that is normal with the 100-400 and 1.4 combo.

I know the autofocus won't work but I was hoping that at least the confirmation light and the beep would still be available.

Leo, I should have made myself more clear, too. Sometimes the light comes on. Sometimes it doesn't. It doesn't seem to have anything to do with focus - I've gotten the light and a blurry picture, and I've gotten "sharp" images without getting the confirmation light.

It might have something to do with the actual size and shape of the AF, maybe?

But you never get the confirmation light.... That's weird.

As a matter of passing interest,

which two contacts do you tape over to get AF back?

I heard of the trick but dont know which contacts it is.

By the way just did a quick test

EOS D30 100- 400L IS and Canon 1.4 TC - definitely no AF, not even the confirmatory beep.

I read the Canon specs that AutoFocus would NOT work even with the 1.4x + 100-400. (following from http://www.usa.canon.c​om/html/eflenses/)

EF 100-400mm f/4.5-5.6L IS USM 140 ~ 560 6.7 ~ 54*1 0.28 O*4*5 (O =possible X =impossible)

*4 AF is ONLY possible with the EOS-1v and EOS-3 cameras, ONLY when using the center focusing point.

I assumed since they didn't list the 10D, the 10D wouldn't work with the 1.4x. Perhaps I'm reading it wrong. Are you using the tape on the contacts to get AutoFocus to work?

iwatkins wrote:
Mind you, I could buy a 100ft 12mm rope, harness, couple of crabs and a figure of eight and abseil down to the nest and use my 50mm lens.

That takes me back to my much younger and stupid days (now just older, still stupid) when I used to rock climb in North Wales. I would bug the heck out of my friends on a face trying to get good shots of them in tricky situations. Now I prefer to hang around in bars instead of rock faces.

Post your results, should be interesting.

North Wales ? Pah, you soft southern jessie. Real men climb in the Peak District or the Lakes.

I used to climb everyday up in Borrowdale when I was young and stupid. Used to be able to lead E3 (or whatever they call it these days). Used to love it, but before my days using cameras (which I still regret).

I'll post some comparisons up once the x2 arrives (tommorrow hopefully). Thanks for the advice Kenny.

Cheers

Ian

I got my 1D MKII yesterday and today I was playing with the 100-400L with a 1.4II TC and lo and behold, the autofocus works without any tape.

Just curious - has anyone considered digiscoping for that extra reach?

Is there such a thing as an MTF for a lens+TC combo? Does Canon publish them? Does anyone actually do the tests?

gordeaux wrote:
I read the Canon specs that AutoFocus would NOT work even with the 1.4x + 100-400. (following from http://www.usa.canon.c​om/html/eflenses/)

What I find interesting from this same chart is that the 400 f5.6L is shown as AF working with the 1.4x without qualification. Big question is "does it?"

dn7elson wrote:

gordeaux wrote:
I read the Canon specs that AutoFocus would NOT work even with the 1.4x + 100-400. (following from http://www.usa.canon.c​om/html/eflenses/)

What I find interesting from this same chart is that the 400 f5.6L is shown as AF working with the 1.4x without qualification. Big question is "does it?"

I have just that combo for testing. I'll give it a try tomorrow and let you know.

That would be great as I am looking at either the 100-400 f4.5-5.6L or the 400 f5.6L when the wallet allows. I can see advantages to both, but if I could "s t r e t c h" the reach a bit more with the 1.4x and still have AF, life would be good.

I find it odd that Canon takes such pains with other lenses to show limited AF or no AF whereas the 400 f5.6 shows AF on the 1.4x chart.