Bokeh is the term for out-of-focus highlights and usually forms rounded circular blobs that mirror the shape of the lens aperture. But the 13-bladed aperture design of the TTartisan 75mm f/1.5 ...

The squeeze factor will also give bokeh an elongated shape, while Sirui says creatives can stay above T/2.4 for a more traditional shape. At T/1.8, bokeh is hexagonal, while at T/2.4, the bokeh is ...