CanonYouCan wrote in post #17687223
I thought the 50mm gave quite a beter bokeh than a 35mm.
I'm not sure comparing one focal length against another is all that relevant for most folks. Longer focal lengths will give more background blur for any set framing and aperture, but that doesn't really speak all that much to the bokeh.
Bokeh is a function of the design of the lens, and a lot of lens features that are good for making a lens sharp and accurate in focus can be bad for bokeh. Specifically, aspherical lens elements and floating lens groups often make for hard-edge blur disks, which make for busy bokeh.
The Canon 50/1.4 and 50/1.8 are examples of fast prime lenses with an ability to really blur a background, but which also have really bad bokeh. Both are very prone to hard-edge blur disks, and the 50/1.8 makes weird pentagons when stopped down.
The Canon 50/1.2L has very good bokeh at any aperture.
The Sigma 50 ART is between these lenses, better than the 50/1.4 (which isn't saying much) but not nearly as good as the 50/1.2L.