- Shadow and highlight enhancement
Shadow and highlight enhancement refers to an
image processingtechnique to correct exposure. Images with over and under-exposed areas can be recovered with the Shadow/Highlight tool in Photoshop. Though this tool can be used to darken overexposed highlights, it is used primarily by professionals to brighten shadow areas.
The use of this technique is becoming more and more popular, making its way onto magazine covers, digital media, and photos. It is, however, considered by some to be akin to other destructive Photoshop filters, such as the Watercolor filter, or the Mosaic filter.
A conservative application of the shadow/highlight tool can be very useful in recovering shadows, though it tends to leave a telltale halo around the boundary between highlight and shadow if used incorrectly. A way to avoid this is to bracket your photo and combine the photos, though, combining bracketed images is difficult, and most of the time requires usage of a tripod.
Recovering highlights with this tool, however, has mixed results, especially when using it on images with skin in them, and often makes people look like they have been "sprayed with fake tan".
Manual Ways to Brighten Shadows
If you are using Photoshop 7 or under, there are many other manual ways in Photoshop to isolate shadow areas and brighten them. One way to do this is to duplicate your background layer, invert the copy and set the
blend modesof that top layer to "Soft Light". You can also use an inverted black and white copy of the image as a mask on a brightening layer, such as Curves or Levels.
Automatic Shadow Recovery Methods
There exist a number of automatic computer image processing-based shadow recovery and
dynamic range compressionmethods that yield a similar effect. Some of these methods include the retinexmethod and homomorphic range compression. The retinex method is based on work from 1963 by Edwin Land, a scientist at Polaroid. [Russ, John C. "The Image Processing Handbook, 5th Ed." CRC Press 2007, pg. 147.]
Shadow enhancement can also be accomplished using adaptive image processing
algorithmssuch as adaptive histogram equalizationor contrast limiting adaptive histogram equalization ( CLAHE).
* [http://www.dpreview.com/reviews/adobephotoshopcs/page2.asp Shadow/Highlight Tool Overview at Dpreview]
* [http://www.digitalproducer.com/2003/10_oct/tutorials/10_27/pscsshadow031028.htm Shadow/Highlight Tutorial]
* [http://www.ronbigelow.com/articles/shadow/shadow-highlight1/shadow-highlight1.htm Ron Bigelow Shadow and Highlight Detail]
Wikimedia Foundation. 2010.
Look at other dictionaries:
Color constancy — Color constancy: The colors of a hot air balloon are recognized as being the same in sun and shade … Wikipedia
Adaptive histogram equalization — is a computer image processing technique used to improve contrast in images. It differs from ordinary histogram equalization in the respect that the adaptive method computes several histograms, each corresponding to a distinct section of the… … Wikipedia
Bibble (software) — Infobox Software name = Bibble developer = Bibble Labs latest release version = 4.10 latest release date = release date|2008|5|9 operating system = Windows, Mac OS X and Linux genre = Photo Post Production license = Proprietary website =… … Wikipedia
Social Protection — ▪ 2006 Introduction With medical costs skyrocketing and government programs scaled back, citizens bore more responsibility for their health care costs; irregular migration, human trafficking, and migrant smuggling posed challenges for… … Universalium
performing arts — arts or skills that require public performance, as acting, singing, or dancing. [1945 50] * * * ▪ 2009 Introduction Music Classical. The last vestiges of the Cold War seemed to thaw for a moment on Feb. 26, 2008, when the unfamiliar strains … Universalium
Australia — /aw strayl yeuh/, n. 1. a continent SE of Asia, between the Indian and the Pacific oceans. 18,438,824; 2,948,366 sq. mi. (7,636,270 sq. km). 2. Commonwealth of, a member of the Commonwealth of Nations, consisting of the federated states and… … Universalium
china — /chuy neuh/, n. 1. a translucent ceramic material, biscuit fired at a high temperature, its glaze fired at a low temperature. 2. any porcelain ware. 3. plates, cups, saucers, etc., collectively. 4. figurines made of porcelain or ceramic material … Universalium
China — /chuy neuh/, n. 1. People s Republic of, a country in E Asia. 1,221,591,778; 3,691,502 sq. mi. (9,560,990 sq. km). Cap.: Beijing. 2. Republic of. Also called Nationalist China. a republic consisting mainly of the island of Taiwan off the SE coast … Universalium
Germany — /jerr meuh nee/, n. a republic in central Europe: after World War II divided into four zones, British, French, U.S., and Soviet, and in 1949 into East Germany and West Germany; East and West Germany were reunited in 1990. 84,068,216; 137,852 sq.… … Universalium
West Lake — Infobox lake lake name = Xī Hú image lake = West Lake.jpg caption lake = image bathymetry = caption bathymetry = location = Hangzhou, Zhejiang coords = coord|30|15|N|120|08|E|region:CN type:waterbody|display=inline,title type = inflow = outflow … Wikipedia