Autofocus point with 1.4x converter

[Bob_Laughton]

Hi all

I've looked all through the manuals and can't find how to select/move the single point AF zone with a 1.4x converter on the 100-400 lens - fine without the converter, but with it on, it seems to disable the shift function. Is this right, or am I missing something?

Cheers


BOB

[Tom_Wilk]

If you're using a 1.4X teleconverter on the 100-400, you have effectively an f/8 lens. With an f/8 lens, only the center focus point is active.

[Bob_Laughton]

Thanks Tom - that explains it clearly. I've not seen that written anywhere though - I must have missed it.

Cheers

BOB

[BobMetzler]

Also note that (at least on my machine) when the center focus point is automatically selected because you mounted the 100-400 lens with 1.4 converter, it is as if you had manually selected that focus point. Even when you change lenses, the center point will remain selected & you'll need to go through the normal procedure to select a different point or auto. I still love it--after six years of having to focus manually with this lens/converter combination!

[Gary_Voth]

The user's guide for the 1.4x should mention this, I believe.

FYI, f/8 AF is only available on 1-series bodies and the EOS-3. As far as I know, Canon's pro models are the only cameras that can do this.