Is doubling in bokeh a lens issue?
Is doubling in bokeh a lens issue? I’ve been looking into buying a Sigma 23mm f1.4 and some example pictures people have taken with it on Flickr. Most of the pictures look OK, but there’s a couple I’ve seen from different users that look like this, where the background blur looks quite busy. More concerning though is that it looks like I’m seeing double in the background, which i…