Product description from Canon. "The EF 24-70mm f/4L IS USM is the perfect zoom to complement full-frame DSLRs like the EOS 6D. With 2 aspheric and 2 UD elements, the EF 24-70mm f/4L IS USM delivers high- quality images with excellent detail throughout the entire zoom range. A 9-blade circular diaphragm delivers beautiful, soft backgrounds.
And here are some sample images from the Canon 5DS R: Canon EOS 5DS R + EF24-70mm f/2.8L II USM @ 35mm, ISO 400, 1/15, f/11.0 Canon EOS 5DS R + EF16-35mm f/4L IS USM @ 23mm, ISO 200, 1/500, f/11.0 Canon EOS 5DS R + EF500mm f/4L IS II USM @ 500mm, ISO 400, 1/3200, f/4.0. In short: detail level is incredible, reminding me of medium format look in The new (September, 2005) Canon 24-105mm f/4L IS is clearly one of these. From the moment I handled a pre-production sample my "gut" told me that this could well be the mid-range zoom that I had been hoping for. Like Bill, I have been using theCanon 24-70mm f/2.8Lfor almost three years. Optically it’s about as fine a fast mid-range zoom as . 173 294 43 481 433 145 362 155