The Japanese photography site Egami uncovered another new Canon patent, the EF-M 600mm f/5.6 DO IS. I am quite comfortable in predicting this patent will most probably never make it to market as is. The thought of a 600mm DO lens mounted on the EOS-M camera can only bring ridicule but it may be modified to fit the future Canon full frame mirrorless camera.
This is clearly Canon's way of staking out their intellectual property by patenting this invention. The current EF 400mm f/4 DO IS II is my favorite Diffractive Optics lens for wildlife photography but there is a chance the EF 600mm f/4 DO BR lens might join its smaller brother next year.
Patent Publication No. 2015-215437
- Published 2015.12.3
- Filing date 2014.5.9
- Focal length 585.00
- F-number 5.74
- Half angle (in degrees) 1.34
- Image height 13.66
- Overall length of the lens 299.25