Editing Bokeh (section)

==Bokeh and lens design==
[[Image:Circles of confusion lens diagram.svg|thumb|right|280px|The [[depth of field]] is the region where the size of the [[circle of confusion]] is less than the resolution of the human eye.]]
Though difficult to quantify, some lenses have subjectively more pleasing out-of-focus areas. "Good" bokeh is especially important for [[macro lens]]es and long [[telephoto lens]]es, because they are typically used in situations that produce shallow [[depth of field]]. Good bokeh is also important for medium telephoto lenses (typically 85–150&nbsp;mm on 35&nbsp;mm format). When used in portrait photography (for their "natural" perspective), the photographer usually wants a shallow depth of field, so that the subject stands out sharply against a blurred background.

Bokeh characteristics may be quantified by examining the image's [[circle of confusion]]. In out-of-focus areas, each point of light becomes an image of the aperture, generally a more or less round disc. Depending on how a lens is corrected for [[spherical aberration]], the disc may be uniformly illuminated, brighter near the edge, or brighter near the center. A well-known lens that exhibited the latter "soap-bubble" characteristic was that produced by Hugo Meyer & Co., more recently revived by [[Meyer Optik Görlitz]].<ref>{{cite web|url=http://www.meyer-optik-goerlitz.com/how-to-create-soap-bubble-bokeh/|author=Blog|title=How to Create Soap Bubble Bokeh|access-date=3 August 2016|archive-url=https://web.archive.org/web/20160725193816/http://www.meyer-optik-goerlitz.com/how-to-create-soap-bubble-bokeh/|archive-date=25 July 2016|url-status=dead}}</ref>

Lenses that are poorly corrected for spherical aberration will show one kind of disc for out-of-focus points in front of the plane of focus, and a different kind for points behind.<ref>{{cite web|url=http://www.bhphotovideo.com/explora/photography/tips-and-solutions/understanding-bokeh/|author=Todd Vorenkamp|title=Understanding Bokeh|access-date=2016-08-03 |archive-date=2016-05-27 |archive-url=https://web.archive.org/web/20160527165827/http://www.bhphotovideo.com/explora/photography/tips-and-solutions/understanding-bokeh|url-status=live}}</ref> This may actually be desirable, as blur circles that are dimmer near the edges produce less-defined shapes which blend smoothly with the surrounding image.
The shape of the aperture has an influence on the subjective quality of bokeh as well. For conventional lens designs (with bladed apertures), when a lens is stopped down smaller than its maximum [[aperture]] size (minimum [[f-number]]), out-of-focus points are blurred into the [[polygon]]al shape formed by the aperture blades. This is most apparent when a lens produces hard-edged bokeh. For this reason, some lenses have many aperture blades and/or blades with curved edges to make the aperture more closely approximate a circle rather than a polygon. Minolta has been on the forefront of promoting and introducing lenses with near-ideal circular apertures since 1987, but most other manufacturers now offer lenses with shape-optimized diaphragms, at least for the domain of portraiture photography. In contrast, a [[Catadioptric system|catadioptric]] [[telephoto lens]] renders bokehs resembling doughnuts, because its [[secondary mirror]] blocks the central part of the aperture opening. Recently, photographers have exploited the shape of the bokeh by creating a simple mask out of card with shapes such as hearts or stars, that the photographer wishes the bokeh to be, and placing it over the lens.<ref>{{cite web|url=http://www.diyphotography.net/diy_create_your_own_bokeh|author=Karsten Stroemvig|title=DIY — Create your own Bokeh|date=25 April 2007|access-date=2009-11-18 |archive-date=2009-12-07 |archive-url=https://web.archive.org/web/20091207203943/http://www.diyphotography.net/diy_create_your_own_bokeh|url-status=live}}</ref>

Lenses with 11, 12, or 15 blade iris diaphragms are often claimed to excel in bokeh quality. Because of this, the lenses do not need to reach wide apertures to get better circles (instead of polygons). In the past, wide aperture lenses (f/2, f/2.8) were very expensive, due to the complex mathematical design and manufacturing know-how required, at a time when all computations and glass making were done by hand. Leica could reach a good bokeh at f/4.5. Today it is much easier to make an f/1.8 lens, and a 9-bladed lens at f/1.8 is enough for an 85&nbsp;mm lens to achieve great bokeh.

Some lens manufacturers including [[Nikon]],<ref>{{cite web|url=http://www.europe-nikon.com/en_GB/product/nikkor-lenses/auto-focus-lenses/fx/single-focal-length/af-dc-nikkor-135mm-f-2d|title=AF DC-Nikkor 135mm f/2D Single Focal Length FX Auto Focus Lenses NIKKOR Lenses|work=europe-nikon.com|access-date=2015-05-01|archive-date=2016-03-05 |archive-url=https://web.archive.org/web/20160305190546/http://www.europe-nikon.com/en_GB/product/nikkor-lenses/auto-focus-lenses/fx/single-focal-length/af-dc-nikkor-135mm-f-2d|url-status=live}}</ref> [[Minolta AF|Minolta]], and [[Sony Alpha|Sony]] make lenses designed with specific controls to change the rendering of the out-of-focus areas.

The Nikon 105&nbsp;mm DC-Nikkor<ref>{{cite web|url=http://www.nikonusa.com/en/Nikon-Products/Product/Camera-Lenses/1932/af-dc-nikkor-105mm-f%252F2D.html|title=AF DC-NIKKOR 105mm f/2D from Nikon|access-date=2013-10-29 |archive-date=2013-10-20 |archive-url=https://web.archive.org/web/20131020154937/http://www.nikonusa.com/en/Nikon-Products/Product/Camera-Lenses/1932/AF-DC-NIKKOR-105mm-f/2D.html|url-status=live}}</ref> and 135&nbsp;mm DC-Nikkor<ref>{{cite web|url=http://www.nikonusa.com/en/Nikon-Products/Product/Camera-Lenses/1935/AF-DC-Nikkor-135mm-f%252F2D.html|title=AF DC-NIKKOR 135&nbsp;mm f/2D from Nikon|access-date=2013-10-29 |archive-date=2013-10-20 |archive-url=https://web.archive.org/web/20131020201703/http://www.nikonusa.com/en/Nikon-Products/Product/Camera-Lenses/1935/af-dc-nikkor-135mm-f/2D.html|url-status=live}}</ref> lenses (DC stands for "Defocus Control") have a control ring that permits the overcorrection or undercorrection of [[spherical aberration]] to change the bokeh in front of and behind the [[Cardinal point (optics)|focal plane]].

The [[Minolta STF 135mm f/2.8 T4.5 lens|Minolta/Sony STF 135&nbsp;mm f/2.8 [T4.5]]] (with STF standing for ''smooth trans focus'') is a lens specifically designed to produce pleasing bokeh. It is possible to choose between two diaphragms: one with 9 and another with 10 blades. An [[apodization]] filter is used to soften the aperture edges which results in a smooth defocused area with gradually fading circles. Those qualities made it the only lens of this kind on the market from its introduction in 1999 to 2014. In 2014 [[Fujifilm]] announced a lens utilizing a similar apodization filter in the [[Fujinon XF 56mm F1.2 R APD lens]].<ref>{{cite web|title=Fujifilm introduces XF 56mm F1.2 R APD with apodization filter|url=http://www.dpreview.com/articles/4106200256/fujifilm-introduces-xf-56mm-f1-2-r-apd-with-apodization-filter|website=DPReview|access-date=2015-05-16 |archive-date=2015-05-31 |archive-url=https://web.archive.org/web/20150531092545/http://www.dpreview.com/articles/4106200256/fujifilm-introduces-xf-56mm-f1-2-r-apd-with-apodization-filter|url-status=live}}</ref> Sony added the [[Sony FE 100&nbsp;mm F2.8 STF GM OSS]] in 2017.<ref>{{cite web |title=Neu von Sony: E-Mount-Objektive 100 mm F2.8 STF GM, FE 85 mm F1.8; Blitz HVL-F45RM |date=2017-02-07 |language=de |work=Photoscala |url=http://www.photoscala.de/2017/02/07/neu-von-sony-e-mount-objektive-100-mm-f2-8-stf-gm-fe-85-mm-f1-8-blitz-hvl-f45rm/ |access-date=2017-02-10 |url-status=live |archive-url=https://web.archive.org/web/20170211003316/http://www.photoscala.de/2017/02/07/neu-von-sony-e-mount-objektive-100-mm-f2-8-stf-gm-fe-85-mm-f1-8-blitz-hvl-f45rm/ |archive-date=2017-02-11}}</ref>

The 'Sigma YS System Focusing' 135&nbsp;mm f/2.8 also has an extra manually-moved component, intended to compensate for aberration at close-focus distances. It can be re-purposed for defocus control.
<ref>{{cite web|url=http://www.4photos.de/test/Bokeh-Defocus-Control.html|author=Markus Keinath|title=Cheap DC Nikkor Substitute|access-date=2013-10-29 |archive-date=2013-10-14 |archive-url=https://web.archive.org/web/20131014164035/http://www.4photos.de/test/Bokeh-Defocus-Control.html|url-status=live}}</ref>

In 2015, [[Meyer Optik Görlitz|Meyer Optik USA Inc.]] launched a [[Kickstarter]] campaign to produce the Trioplan f2.9/50, a new lens based on one originally produced by Hugo Meyer & Co.; both lenses exhibit a characteristic "soap-bubble" bokeh.<ref>{{cite web|url=http://en.globell.com/Meyer-Optik-brings-back-legendary-Trioplan-f2.8-100-soap-bubble-bokeh-lens-with-Kickstarter-campai_detail_968_2236.html|author=Meyer-Optik-Görlitz / net SE|title=Meyer Optik brings back legendary Trioplan f2.8/100 'soap bubble' bokeh lens with Kickstarter campaign|access-date=2016-08-03|archive-url=https://web.archive.org/web/20160818100516/http://en.globell.com/Meyer-Optik-brings-back-legendary-Trioplan-f2.8-100-soap-bubble-bokeh-lens-with-Kickstarter-campai_detail_968_2236.html|archive-date=2016-08-18|url-status=dead}}</ref>

The use of [[anamorphic]] lenses will cause bokeh to appear differently along the horizontal and vertical axes of the lens, becoming ellipsoidal compared to those in a spherical lens.

In 2016, [[Apple Inc.]] released the [[iPhone 7 Plus]] which can take pictures with "Portrait Mode" (a bokeh like effect).<ref>{{Cite news|url=https://petapixel.com/2016/10/24/apple-just-released-fake-bokeh-portrait-mode-everyone/|title=Apple Just Released Their Fake Bokeh Portrait Mode to Everyone|date=2016-10-24|work=PetaPixel|access-date=2017-11-28|language=en-US|archive-date=2017-12-12 |archive-url=https://web.archive.org/web/20171212190031/https://petapixel.com/2016/10/24/apple-just-released-fake-bokeh-portrait-mode-everyone/|url-status=live}}</ref> Samsung's [[Galaxy Note 8]] has a similar effect available. Both of these phones use dual cameras to detect edges and create a "depth map" of the image, which the phone uses to blur the out-of-focus portions of the photo. Other phones, like the [[Google Pixel]], only use a single camera and machine learning to create the depth map.<ref name="How Portrait Mode Works">{{cite web |last1=Simpson |first1=Jayphen |title=How Portrait Mode Works and How It Compares to an $8,000 Camera |url=https://petapixel.com/2017/12/11/portrait-mode-works-compares-8000-camera/ |website=PetaPixel |access-date=11 December 2017 |date=11 December 2017 |archive-date=2018-06-04  |archive-url=https://web.archive.org/web/20180604233929/https://petapixel.com/2017/12/11/portrait-mode-works-compares-8000-camera/ |url-status=live }}</ref>

In 2017, [[Vivo (smartphone)|Vivo]] released a smartphone with dual front lenses for [[selfie]]s with bokeh. The first, a 20 MP lens, uses a 1/2.78" sensor with f/2.0 aperture, while the second, an 8 MP f/2.0 lens, captures depth information. Bokeh can be made with a combination of both lenses, and shots can be refocused even after they are captured, adding bokeh effects with different depths.<ref>{{cite web |url=http://www.gsmarena.com/vivo_v5_plus_becomes_official_with_dual_front_camera_snapdragon_625-news-22831.php |title=vivo V5 Plus becomes official with dual front camera, Snapdragon 625 |date=January 18, 2017 |access-date=2017-02-07  |archive-date=2017-02-08  |archive-url=https://web.archive.org/web/20170208033207/http://www.gsmarena.com/vivo_v5_plus_becomes_official_with_dual_front_camera_snapdragon_625-news-22831.php |url-status=live }}</ref>

In early 2018, the [[Honor (brand)|Honor]] 9 Lite smartphone was released with quad cameras (two dual-lens). Both the front and back cameras have a 13&nbsp;MP main lens and a 2&nbsp;MP lens for capturing bokeh depth information.<ref>{{cite web |url=https://www.androidauthority.com/honor-9-lite-review-830795/ |title=Honor 9 Lite review: four lenses on a budget |author=ABHISHEK BAXI |access-date=March 30, 2018 |date=February 8, 2018 |archive-date=2018-03-30  |archive-url=https://web.archive.org/web/20180330143853/https://www.androidauthority.com/honor-9-lite-review-830795/ |url-status=live }}</ref>

<gallery widths="220" heights="160">
File:DOF-ShallowDepthofField.jpg|An extremely shallow [[depth of field]], a common effect in [[macrophotography]], emphasizes bokeh.
File:Thumbs up for bokeh.JPG|200&nbsp;mm lens at [[F-number|f/2]].
File:Catadioptric lens bokeh etc - 2018 12 08.webm|[[Catadioptric system|Catadioptric lens]] bokeh in motion.
File:Bahnhof Dortmund Brackel Spiegeltele DSC02359 smial wp.jpg|The bokeh produced by a [[Catadioptric system|catadioptric lens]] (also called a mirror lens).
File:Bokeh Example.jpg|An example of the bokeh produced by the Canon 85&nbsp;mm prime f/1.8 lens. The polygonal shapes are due to the 8-bladed aperture diaphragm being slightly closed. At its full aperture ([[F-number|f/1.8]]) these shapes would be smooth and not polygonal.
File:Donut bokeh.jpg|[[Catadioptric system|Catadioptric lens]] bokeh seen in more detail.
File:Christmas Tree Lights Bokeh.jpg|An example of the creative application of bokeh.
File:Bokeh.JPG|An example of the bokeh produced by the Canon 18–55&nbsp;mm f/3.5–5.6 IS II lens.
File:Bokeh1 DSC 0959.jpg|A bokeh created with Nikon D3300 Camera 18–55&nbsp;mm f/3.5–5.6 G VR II Lens.
File:Photography by Victor Albert Grigas (1919-2017) 000172050002 (37159721864).jpg|Subtle swirly bokeh in the background
File:Christmas Tree out of focus copy.jpg|Swirly bokeh
File:Bad Bokeh Background.jpg|Picture of ''[[Forsythia]]'' with doughnut-shaped background bokeh, due to the use of a catadioptric system. Focus on foreground.
File:Bad Bokeh 02.jpg|Picture of ''[[Forsythia]]'' with doughnut-shaped foreground bokeh, due to the use of a catadioptric system. Focus on background
File:Silicon Valley background Samsung Galaxy S22 Ultra.jpg|[[Silicon Valley]] background/bokeh shot with [[Samsung Galaxy S22]] Ultra smartphone
File:Out of focus.png|alt=Bokeh on a cherry tree's leaves created by the Samsung Galaxy A54's main camera|Bokeh created by the [[Samsung Galaxy A54 5G|Samsung Galaxy A54]]'s main camera
</gallery>