Bokeh is a Japanese-origin term used in photography and rendering to describe the visual quality of the out-of-focus areas in an image. It's not the same as blur itself — bokeh is specifically about the character of the blur. Smooth round soft-edged blur is considered good bokeh; harsh-edged or distracting blur is considered bad bokeh. The shape of the bokeh blobs from point lights (round, hexagonal, octagonal) is determined by the camera's aperture blades.
In architectural rendering, bokeh shows up most prominently when there's strong point lighting in the background of a shallow depth-of-field shot — for example, an interior render with city lights visible through a window at night, or a Christmas tree with lights in the background. The points of light render as soft glowing disks of bokeh that contribute substantially to the mood of the image.
AI rendering produces bokeh implicitly when you specify shallow depth of field, but you can also call it out directly. 'Soft circular bokeh in the background from string lights' or 'creamy bokeh from the window' will push the AI to emphasize the effect. For pure architectural shots without background point lights, bokeh isn't relevant — but for night shots, evening interiors, or product-focused renders it can be the difference between a flat shot and a striking one.
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