SUMMARY
Bokeh, derived from the Japanese word for blur, describes the visual quality of out-of-focus areas in a photograph. It is distinct from depth of field, which controls the amount of blur. Factors like aperture shape, lens design, and background elements influence whether bokeh appears smooth and creamy or harsh and distracting. Pleasing bokeh often features round, clean out-of-focus highlights and smooth tonal transitions, while undesirable bokeh can exhibit polygonal shapes, color fringing, or nervous double-lines.
TAKEAWAYS
Bokeh is the quality, not the quantity, of background blur.
Lens design and aperture shape are key factors in bokeh quality.
Pleasing bokeh has smooth highlights and tonal transitions.
Bad bokeh can manifest as harsh shapes, color fringing, or double-lines.