Sigma 120-300mm f/2.8 DG OS HSM Performance at 300mm, Close Range (Canon 5D Mark III)
To my review coverage on the Sigma 120-300mm f/2.8 DG OS HSM S is added a 300mm full aperture series from f/2.8 through f/16.
This series is interesting for bokeh, sharpness and color correction.
Sigma 120-300mm f/2.8 is available at B&H Photo for about $3599 for Canon and about $3599 for Nikon. Caution as there are older versions (different design) for $2499.