The Complete Guide to FD Lenses for Mirrorless Cameras (m43, NEX, EOS-M, etc.) Legacy lenses have seen a resurgence with the popularity of mirrorless cameras, today we’ll be focusing on one of the most popular legacy lens mounts – Canon’s FD mount. And while this is primarily a website covering Micro Four Thirds, this could apply to many other systems. Even Canon’s current EF mount, though not without it’s fair share of drawbacks that don’t quite exist with mirrorless cameras, Lemming51 on DPReview points out: Canon FD/FL lenses had a shorter mounting distance than the EF EOS design.
So mounting these lenses to an EOS camera with a simple ring adapter does effectively apply extension, which makes them closer focusing (good for macro), but makes it impossible to focus beyond a meter or 2. Typical FD to EOS adapters have corrective lens elements to restore infinity focus, but these necessarily also act as a 1.26x teleconverter that results in the loss of 2/3 stop maximum aperture and degraded image quality. Pros and Cons of Using an FD Lens Pros Cons Which FD Adapter?