# Converters on a 7D



## dogwatch (Dec 13, 2012)

Hi, My gear on safari trips is a 7D, 70-200mm f2.8 & 100-400mm lenses plus 1.4 & 2.0 converters (& a selection of W/A etc).
No problem in autofocus without the converters BUT,
Is there any way I can get the 100-400mm lens to autofocus with a converter on?


----------



## AlanF (Dec 13, 2012)

I have tried the 7D with the 100-400 using both the Kenco DG Pro 1.4x, which is non-reporting TC, and with the Canon 1.4x III, by taping two of the pins. The results are not good. In bright light they will focus but in poorer conditions they have been erratic. I would not recommend their use.


----------



## Michael_pfh (Dec 13, 2012)

There's always the option to put tape over certain pins to enable the AF. You can for sure google the instructions on that trick...


----------



## Deleted member 91053 (Dec 15, 2012)

You can tape pins, get a non reporting extender, focus in live view etc etc. When I had the 100-400 I tried extenders and, frankly, it was not worth it IMO. You really need an F4 lens or better if you want to use extenders. My 1D4 will af at F11 but generally it's a pointless exercise as you won't want to keep the image.


----------



## Don Haines (Dec 16, 2012)

If you use the sigma extender it will autofocus, but the image is degraded. On my setup the 100-400 resolves more detail without the extender, so I tend to leave the extender home.


----------



## dogwatch (Dec 20, 2012)

Thanks for the info. Had a suspicion that it would not work but worth asking.


----------



## Forceflow (Dec 21, 2012)

Don Haines said:


> If you use the sigma extender it will autofocus, but the image is degraded. On my setup the 100-400 resolves more detail without the extender, so I tend to leave the extender home.



Really? Which Extender do you use? I have the 2x and it will not focus for the live of it. (It wont even focus on my Sigma 150mm 2.8 which it really should be able to  )


----------



## dwe (Dec 21, 2012)

I have no problems at all  has anyone ever tried to use live view and focus with the af button on an 7D?
Works with a 100-400 and a 2x converter. in poor light it will hunt some but it will focus.

don't consider shooting out of the hand btw use a tripod for the 1280mm u are using....
u can make excellent pictures of the moon like this

Dennis


----------

