Optical Specs

• Increase maximum aperture by 1 stop. (with a maximum output aperture of f/0.9).
• Increase MTF (details).
• Makes lens 0.71x wider.
• Advanced 5-element/4-group optical design incorporating ultra-high index tantalum-based optical glass by Caldwell Photographic in the USA (patent granted).

Electronic Specs

• Canon EF mount lens to Fujifilm X-mount camera.
• Autofocus. Phase-detection autofocus (PDAF) is supported no matter which AF lens is used. Adapters support PDAF by translating pertinent metadata about the optics between the lens interfaces. In this way, broad support of the widest range of lenses is made possible.
• Lens iris/aperture is set by the controls on the camera body.
• Fujifilm XF Teleconverters support.
• Optical image stabilization (IS) lens support.
• Smooth iris support with the latest Canon (2009+), Tamron (SP series 2013+) and Sigma (2016+) lens models.
• Focal length and aperture are adjusted in EXIF (see note 3).
• Store EXIF data (lens name, focal length and maximum/minimum aperture) for one manual lens in the adapter.
• Parallax correction on the X-Pro series rangefinders is also supported.
• LED indicator shows communication status. 
• Powered by camera body. With most lenses, no external power source required.