Bokeh

Coarse bokeh on a photo shot with an 85 mm lens and 70 mm entrance pupil diameter, which corresponds to f/1.2
An example of a portrait photo (of Katherine Maher). Note the 'swirly' bokeh.
How the bokeh varies with the aperture.

In photography, bokeh (/ˈbkə/ BOH-kə or /ˈbk/ BOH-kay;[1] Japanese: [boke]) is the aesthetic quality of the blur produced in out-of-focus parts of an image, whether foreground or background or both. It is created by using a wide aperture lens.

Some photographers incorrectly restrict use of the term bokeh to the appearance of bright spots in the out-of-focus area caused by circles of confusion.[2][3][4] Bokeh has also been defined as "the way the lens renders out-of-focus points of light".[5] Differences in lens aberrations and aperture shape cause very different bokeh effects.[6] Some lens designs blur the image in a way that is pleasing to the eye, while others produce distracting or unpleasant blurring ("good" and "bad" bokeh, respectively).[6] Photographers may deliberately use a shallow focus technique to create images with prominent out-of-focus regions, accentuating their lens's bokeh.

Bokeh is often most visible around small background highlights, such as specular reflections and light sources, which is why it is often associated with such areas.[6] However, bokeh is not limited to highlights; blur occurs in all regions of an image which are outside the depth of field.

The opposite of bokeh—an image in which multiple distances are visible and all are in focus—is deep focus.

  1. ^ Nikon (2017-03-30), Bokeh for Beginners, archived from the original on 2019-07-24, retrieved 2019-07-24
  2. ^ Gerry Kopelow (1998). How to photograph buildings and interiors (2nd ed.). Princeton Architectural Press. pp. 118–119. ISBN 978-1-56898-097-3. bokeh focus.
  3. ^ Roger Hicks and Christopher Nisperos (2000). Hollywood Portraits: Classic Shots and How to Take Them. Amphoto Books. p. 132. ISBN 978-0-8174-4020-6.
  4. ^ Tom Ang (2002). Dictionary of Photography and Digital Imaging: The Essential Reference for the Modern Photographer. Watson–Guptill. ISBN 0-8174-3789-4.
  5. ^ "PhotoWords/Lens". PhotoGuide Japan. Archived from the original on 2018-12-26. Retrieved 2009-10-30.
  6. ^ a b c Harold Davis (2008). Practical Artistry: Light & Exposure for Digital Photographers. O'Reilly Media. p. 62. ISBN 978-0-596-52988-8.