Bokeh (Photographic Concept)
Bokeh (pronounced /ˈboʊkə/ BOH-kə or /ˈboʊkeɪ/ BOH-kay) is a loanword from Japanese that, in photography, denotes the aesthetic quality of the blur produced in the out-of-focus areas of an image. It has become the standard international term for describing the character and visual effect of this blur, which is influenced primarily by the optical design of a camera lens.
Table of Contents
- Etymology & Linguistic Origin
- History & Conceptual Development
- Technical Basis & Lens Characteristics
- Qualitative Judgment: “Good” vs. “Bad” Bokeh
- How to Achieve & Influence Bokeh
- Cultural Impact & Usage Beyond Photography
- Related Terms
- References & Further Reading
1. Etymology & Linguistic Origin {#etymology}
The term “bokeh” is a romanization of the Japanese word “boke” (暈け or ぼけ), which is the noun form of the verb “bokeru” (暈ける or ぼける).
- Linguistic Meaning: The verb “bokeru” translates to “to be blurry,” “to be out of focus,” or “to be mentally fuzzy.” The noun “boke” simply means “blur” or “blurriness.”
- Kanji Significance: The kanji “暈” (un or kasumi) means “halo,” “fringe,” or “ring,” which aptly describes the gradual fading at the edges of an out-of-focus point—a central characteristic of the bokeh effect.
2. History & Conceptual Development {#history}
The evolution of “boke” from a general term for blur to a specific photographic concept occurred in the late 20th century within Japanese photographic journalism.
- The Japanese Innovation: In the 1980s and 1990s, reviewers in Japanese photography magazines (notably Photo Technic) began using the compound term “boke-aji” (ボケ味) to critique lenses.
- Boke (ボケ): Blur.
- Aji (味): Taste, flavor, quality.
- Thus, “boke-aji” translated to “the taste (or quality) of the blur.” This marked the shift from describing the presence of blur to critiquing its aesthetic character.
- Introduction to the English Lexicon: The term was formally introduced to English-speaking photographers by editor Mike Johnston in the March/April 1997 issue of the U.S. magazine “Photo Techniques.” His article, “Bokeh: What is it? What makes it good or bad?,” imported the entire qualitative concept, spelling it as “bokeh” to suggest the correct Japanese pronunciation.
3. Technical Basis & Lens Characteristics {#technical}
Bokeh is a property of the out-of-focus areas in an image, which exist outside the depth of field (DOF). Its appearance is determined by the lens’s optical design, specifically:
- Spherical Aberration Correction: Lenses corrected to render out-of-focus points as uniform discs tend to produce “smoother” bokeh.
- Aperture Blade Design: The number and shape of the aperture blades affect the shape of out-of-focus highlights. More rounded blades create more circular “bokeh balls”; straight blades create polygonal shapes (e.g., heptagons, octagons).
- Lens Formula: Different optical designs (e.g., double-Gauss, Sonnar) have characteristic bokeh “signatures,” sometimes including swirling or “cats-eye” effects near the image corners.
4. Qualitative Judgment: “Good” vs. “Bad” Bokeh {#qualitative}
Photographers subjectively evaluate bokeh quality, often using terms directly derived from the original Japanese critique:
| Judgment | Japanese Term | Photographer’s Description | Visual Characteristics |
|---|---|---|---|
| Favorable | 良いボケ (Yoi Boke) | “Creamy,” “smooth,” “buttery,” “pleasing.” | Soft, diffuse circles; gradual transitions; background is unobtrusive. |
| Unfavorable | 悪いボケ (Warui Boke) | “Harsh,” “busy,” “nervous,” “distracting.” | Double-edged “onion rings”; visible hard-edged polygons; distracting texture. |
5. How to Achieve & Influence Bokeh {#achieve}
The prominence and quality of bokeh are controlled by photographic technique, primarily through manipulating depth of field:
- Use a Large Aperture: Set the lens to its widest opening (lowest f-number, e.g., f/1.4, f/1.8).
- Increase Focal Length: Use a longer lens (e.g., 85mm or 135mm vs. 35mm).
- Minimize Focus Distance: Get closer to your subject.
- Maximize Background Distance: Increase the separation between your subject and the background.
- Choose a Suitable Background: Backgrounds with small, high-contrast points of light (e.g., distant lights, sun through foliage) make the bokeh effect most visible.
6. Cultural Impact & Usage Beyond Photography {#impact}
- Smartphone Technology: Computational photography features like “Portrait Mode” simulate the bokeh effect using software and dual lenses.
- Cinematography: The intentional use of shallow depth of field and pleasing bokeh is a staple of cinematic language to isolate subjects and create mood.
- Graphic Design: Digital bokeh effects are common in advertising, web design, and music visuals to convey a sense of warmth, professionalism, or festivity.
7. Related Terms {#related}
- Depth of Field (DOF): The distance between the nearest and farthest objects that appear acceptably sharp.
- Aperture: The opening in a lens that controls the amount of light and depth of field.
- Spherical Aberration: An optical imperfection affecting how a lens focuses light, directly influencing bokeh quality.
- Circle of Confusion: The optical term for the blur spot created by a point source when it is not perfectly in focus; the rendering of these circles defines bokeh.
8. References & Further Reading {#references}
- Johnston, M. (March/April 1997). “Bokeh: What is it? What makes it good or bad?” Photo Techniques.
- Editorial Staff. (Various issues, 1990s). Lens Reviews. Photo Technic (日本写真企画出版).
- Bokeh.” Wikipedia, The Free Encyclopedia. Wikimedia Foundation.
- van Walree, P. “Bokeh.” Paul van Walree’s Photographic Optics. (Technical online resource).
- Takahashi, K. (2010). The Art of Lens Design: A Japanese Perspective (in Japanese). Gijutsu Hyōronsha.
Disclaimer: This is a synthesized, wiki-style informational guide. For the definitive and collaboratively edited reference, please visit the Wikipedia entry for “Bokeh.”
