# Kenko 1.4x teleconverter, 7dii & Sigma 50-500 - will it work?



## ashley (Dec 26, 2014)

Tried both a Sigma & Canon 1.4 converter with my Bigma 50-500mm and neither got the autofocus to work (the Canon didn't even fit the lens!), so has anyone tried a Kenko 1.4 converter with this lens/camera combo and got the autofocus to work ?

(the 7dii is meant to auto-focus at f8 and I know the Bigma is actually a 6.3 but pretends its a 5.6 to get the autofocus to work)

Thanks,

Ashley


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## GMCPhotographics (Jan 5, 2015)

ashley said:


> Tried both a Sigma & Canon 1.4 converter with my Bigma 50-500mm and neither got the autofocus to work (the Canon didn't even fit the lens!), so has anyone tried a Kenko 1.4 converter with this lens/camera combo and got the autofocus to work ?
> 
> (the 7dii is meant to auto-focus at f8 and I know the Bigma is actually a 6.3 but pretends its a 5.6 to get the autofocus to work)
> 
> ...



I found the 50-500 bigma slightly soft when shooting wide open at 500mm on a full frame. So putting it on a 1.6x crop and slotting a 1.4x tc isn't going to improve it's softness at all. To be honest, I think you are asking too much from this lens. Good luck with even getting that combo to AF accurately even in bright light. Even more good luck in getting it stable on a tripod with those kinds of focal lengths.


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## Mt Spokane Photography (Jan 5, 2015)

The Kenko 1.4X TC does not work on recent Canon cameras for certain lenses, I've not seen a list yet for the 7D MK II, or seen anything on the forums about issues with this lens plus a TC on a 5D MK II.

You may be better off going for the Tamron 150-600, as far as getting a longer focal length.

About all you can do with regard to the Kenko, is to buy one somewhere that accepts returns in the event it does not work.

As noted, TC's work best on a sharp lens, and magnify any flaws, so that might be a consideration.

Another possibility in the low price range is a good copy of the 100-400mm L MK I. It accepts TC's and is good with them.


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## ashley (Jan 10, 2015)

Thanks for the replies.

I plan on saving up for either the 400mm 5.6 prime with a 1.4 TC (I hear its a good lens) or maybe even the new 100-400 L II thats just come out.

Thanks,

Ashley


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## mistercactus (Jan 10, 2015)

BTW, Kenko 1.4 TC won't work with Canon 100-400L Mk1, unless you tape 3 of the pins between TC & lens. Plus, image quality will be mediocre @ best!


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