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mariusnagy
24th of May 2004 (Mon), 03:32
Does somebody tried this combination? :lol:
Does the central auto focus point work with this configuration? :roll: Could you provide some samples with quality changes with and without 1.4x converter for 100-400L? :wink:
defordphoto
24th of May 2004 (Mon), 05:26
You will lose autofocus completely with this combination. There is a way to tape over some contacts on the lens that will allow it to autofocus with very mixed results. Viewfinder also gets pretty dark. Otherwise it's a decent combo and you will get some very nice shots using it.
mariusnagy
24th of May 2004 (Mon), 07:19
Ok, so actually the converter is the one who stop the auto focus :twisted: is not just some lost capability of the camera due to the low light.
Interesting! :lol:
defordphoto
24th of May 2004 (Mon), 07:48
Ok, so actually the converter is the one who stop the auto focus :twisted: is not just some lost capability of the camera due to the low light.
Interesting! :lol:

Yes. Once the converter is on the camera, the camera "knows" it's there and shuts down autofocus.
dn7elson
24th of May 2004 (Mon), 07:54
Yes. Once the converter is on the camera, the camera "knows" it's there and shuts down autofocus.

So, this would seem to point that the camera AF sometimes can and other times can't AF at below f5.6 if the tape trick sometimes works. Likely why it makes the choice it does since it cannot be counted upon to reliably and quickly (or reasonably so) AF at that effective aperture.
cgratti
24th of May 2004 (Mon), 12:47
Ok, so actually the converter is the one who stop the auto focus :twisted: is not just some lost capability of the camera due to the low light.
Interesting! :lol:

Yes. Once the converter is on the camera, the camera "knows" it's there and shuts down autofocus.

Does a converter affect lenses with IS too?