Airbus3463 years ago000I use a Canon R6 with the RF 100-400 F5.6-8 IS USM. Can I use the Canon EF 1.4x III.Show in original language (German)Kamil Taylan3 years ago000 Helpful answerI don't know exactly, but I don't think so. I use the combination EF and M. It works. You can get an answer to this question at the Canon Shop.Show in original language (German)Commentteodorwick3 years ago000No, unfortunately you can't.Show in original language (German)Comment