Whitebalance in Photography
by Ginny Ashton
White balance adjustment means to adjust the light in a photo to white. In order to do this you must have a neutral in the image like a gray card or a white sheet of paper. Software can correct white balance, but not all software is equally good.
The first thing you might like to take care of, when you want to edit your pictures, is white balance. White balance refers to the color of the light and assumes that the optimal light color is white. Some pictures, like sunset or candlelight, do not have white light, but in general an impression of white light is good. Some use Photoshop's auto levels to set white balance, but that is not ideal, since auto levels just sets the darkest areas to black and the brightest to white without looking at the mid tones. But what if the lightest pixel in your photo is not white? Or what if you do not have pure black in the photo? (Most pictures have black areas, but the palest pixels are rarely pure white).
When correcting white balance, the mid tones are the most important and to help set the mid tones correctly one adds a grey card to the photo when taking the picture. A grey card is a sheet of cardboard or plastic of an exact mid tone neutral gray. Ideally one has three cards: a black, a gray and a white. Photoshop's levels adjustment panel has three color pickers for picking color: one for white, one for gray and one for black. By clicking the gray color picker on the gray card, one can adjust the mid tones to neutral gray. One can of course only include a gray card in the image if one intends later to crop the photo.
If one does not want a gray card in the image, or if one doesn't have a gray card at hand, one can later use dedicated software that analyzes the image and calculates the color of the light and sets it to white. There are draw backs with such software: what if there are no neutral areas in the image to calculate the color of the light from? Some applications do not need a neutral in the picture, but most do to get a good result.
When working with RAW images, you will have discovered that the RAW converters generally come with a control for color temperature, meaning a control to adjust the image cool or warm. But what if the color of the light is greenish as when you have taken a picture in fluorescent light? The cool-warm control is good for regular incandescent light, but not for fluorescent.
Color adjustment sliders are rarely good for correcting white balance, because the color adjustment will not just neutralize the gray card, but will also tone the image in an undesirable way: often the blacks get colored or the whites or both. In short one needs some neutrals in an image to correct white balance. A white wall or a piece of white paper will suffice; at best add a gray card for the mid tones.
Source: <a href="http://www.articlesbase.com/digital-photography-articles/white-balance-what-is-it-6540040.html">Whitebalance in Photography</a>.
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New Unique Article!
Title: Whitebalance in Photography
Author: Ginny Ashton
Email: jan@janesmann.com
Keywords: Whitebalance,Digital photography,Hobbies, arts and entertainment
Word Count: 524
Category: Hobbies
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