Canon EF 1.4x Extender with EF 100-400L is lens

Location : N E Jockistan Spotter Watch Member : No

I have used the EF 100-400L is lens for a number of years and love it. I'm toying with buying the EF 1.4x Extender to use with this lens. A couple of questions:

1. Are there any known issues with the 100-400L is/1.4x extender combination on EOS 40D?

2. How are the combination used, i.e. fit extender to lens and then both to body, or fit extender to body and then add lens?

I would welcome advice/opinions from members who use this combination of kit. I assume there is full AF connectivity as the max aperture of the lens is f4.0

Thanks

Admin Location : Bristol, UK

You will lose autofocus if you attach the Canon EF 1.4x to the 100-400L, but there is a way around it - By taping over the contacts, however I've heard the Auto Focus is very slow and in-accurate (I use Nikon, so cannot comment from first hand). Hopefully someone will have used this combo and trick first hand and can comment.

Regarding attaching the teleconvertor, it doesn't matter which way you do it. I personally tend to attach my TC to my camera then the lens to the TC - But whichever way is quickest and easiest for you.

Location : Mildenhall

Quote :: You will lose autofocus if you attach the Canon EF 1.4x to the 100-400L, but there is a way around it - which is taping over the contacts, however I've heard the Auto Focus is very slow and in-accurate

Spot on.
I have the 100-400 and the 1.4....it is a waste of time putting the extender on it.
(At least it is on the 30D...not sure about other cameras)
Dave.

Location : Lincolnshire

I cant comment on the 100-400 and 1.4x convertor combiHowever, I have a 70-200 2.8 IS and 1.4x convertor and cannot fault the combination. You lose around one f stop and the auto focus is not affected at all.
As for attachment, the instructions state that you should attach the convertor to the lens and then fit the combined system to your camera.
My EP-3E images from Mildenhall were taken with this combination and I was more than happy with the results.

http://fightercontrol.forumotion.com/recent-photos-f3/ep-3e-mildenhall-t13616.htm

Hope this helps,

Dinger.

Location : N E Jockistan Spotter Watch Member : No

If AF is lost, I'm inclined to forget the idea - I'm not interested in the extender if it's not full compatible. I hadn't realised this was the case, it's a shame the max aperture of the 100-400L is f.4.5 instead of f4.0

Sad

Location : Mildenhall

Quote :: it's a shame the max aperture of the 100-400L is f.4.5 instead of f4.0

It's actually 5.6 at 400 mm....so even worse.
Dave.

Location : N E Jockistan Spotter Watch Member : No

Thanks for the replies guys, problem solved. I will not be buying the Canon EF 1.4x Extender.