fes22 wrote:
I am considering a Canon Extender ef 2X lll for use on a 70-200 f4L lens. I have a Canon 6d. Does anyone have experience, and opinion with this combination. I am currently using a 70-300L as a long lens, but I would really like to cut back on weight.
You will lose autofocus on a F4 with a 2X Canon extender unless you own a 5D3 with the appropriate firmware or some of the 1D series. Your 6D isn't in the list to overcome the f8 limitation. You can buy an aftermarket extender that should solve this limitation.