A patent showing a lens design from that shows the ability to reverse mount for greater macro magnification has appeared.
Patent publication number 2016-206568 (Google Translated)
- Release date 2016.12.8
- Application date 2015.4.28
- Reversibly attachable lenses
- Reverse attachment detection switch
- Switch control according to installation position
There have been a few adaptors over the years that would allow you to reverse mount certain lenses for macro usage.
Egami suggest that this patent may have been part of the EF-M 28mm f/3.5 IS Macro lens development.