A patent showing an optical formula for an EF 11mm f/4 has appeared, and we think it was likely part of the EF 11-24 f/4L development.
Patent Publication No. 2016-81005 (Google Translated)
- Published 2016.5.16
- Filing date 2014.10.22
- Focal length 11.33 11.47
- F-number 4.11 4.12
- Half angle of 62.36 62.08
- Image height 21.64 21.64
- Overall length of the lens 109.13 109.12
- BF 38.90 38.40
I don't think we're going to see such a lens from Canon.