Canon 7d mark 11 locks up, no autofocus with Canon 500 F4 IS I and 1.4x teleconverter attached.

[pat4ster]

When I mounted my Kenko Pro 300 1.4x teleconverter to my Canon 500 F4 IS I lens I got no focus at all. The lcd is frozen, no shutter release or auto focus!  I then reset all in camera settings I made and then powered off and repowered and then it worked. What add on settings that I did would make auto focus with 1.4x not work?  Thanks

Pat

[ezpop]

Kenko Pro 300 1.4X comes with different versions. Older versions did have some compatibility problem. The newer ones are DG and DGX.

You may have to wait for an updated version of  teleconverter with a firmware compatible to your 7D2 if it is unstable for operation.

http://kenkoglobal.com/pdf/TELEPLUS_DGX_series_CompatibilityList.pdf

[pat4ster]

Thanks! My Kenko  is the DGX model

Pat

[ebiggs1]

Not only is is not compatibile, stop using it.  It may damage your new camera.  It is best to use a real genuine Canon tele-converter.  You have  a top drawer camera and lens, dont' skimp now on the converter.  IMHO, as always. 

[Bajadreamer]

I know this is an old thread but I have a similar problem. I have a 70D with a Canon 400/5.6 lens. The first time I used a Kenko 1.4 DGX, it worked fine. The 2nd time, it locked up similar to yours. When I took the Kenko off, and just used the 400, it would remain locked up until I took the battery out and then reinserted the battery.
Any thoughts?

[ebiggs1]

"Not only is is not compatibile, stop using it.  It may damage your new camera.  It is best to use a real genuine Canon tele-converter.  You have  a top drawer camera and lens, dont' skimp now on the converter."

The camera only resets itself whne you remove the battery.

[TCampbell]

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@Bajadreamer wrote:
I know this is an old thread but I have a similar problem. I have a 70D with a Canon 400/5.6 lens. The first time I used a Kenko 1.4 DGX, it worked fine. The 2nd time, it locked up similar to yours. When I took the Kenko off, and just used the 400, it would remain locked up until I took the battery out and then reinserted the battery.
Any thoughts?

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If you have to remove the battery to reset it, it means you have effectively "crashed" the camera's firmware by giving it a situation that it was never designed to handle.  

Canon does not publish their lens communication specifications to third parties (no camera vendor that I know of shares their protocol specs.)  That means companies like Kenko have to try to "reverse engineer" what is expected by the camera & lens.  If they get that wrong, they can crash the firmware and cause problems.

The power switch on the camera is really a "soft" switch.  It simply tells the computer that you'd like to "shut down" -- but does not actually deprive the camera of power.  This is why the camera can perform a self-clean cycle and you see the brief message on the LCD screen (if it really deprived power, the camera would go dark instantly.)   But if the firmware is "crashed" it cannot respond to the soft switch.  Hence ejecting the battery is the only way to actually deprive the camera of power so that it has to boot fresh when you re-insert the battery (the folks who publish the "Magic Lantern" firmware caution that if the camera ever locks up, the only safe way to reset it is to eject the battery -- for this very reason.)

As ebiggs has already mentioned, this unfortunately means that your teleconverter is not compatible with your camera and lens and should not be used.  

[Bajadreamer]

Thank you.  Won't do that again.  I was relying on advice from Adorama that said the Kenko would work, albeit only in bright light where the F8 would not be a factor.

I did find that Canon has a "auto lock" feature that will not allow the camera to operate, at least not in autofocus, when F8 or small aperatures are all that are available.

Thanks again

Jim