I think this is an important note and often overlooked with the CY lenses. Wanted to love some of their fast ones, but too often found myself wanting to shoot at f/2 for a bit more sharpness, and was rewarded with hexagon OOF points that ruined what otherwise would be great bokeh. Its a shame...
Samuli Vahonen wrote:
Samuli Vahonen wrote about C/Y Sonnar 2.8/135 some weeks ago from this thread:
Hexaconal boke highlights are awful - in many scenes the background boke turns pretty ugly at any other aperture than f/2.8. Wide open boke is always extreme good (personal opinion).
Samuli