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 work on, when you begin to edit your images, is white balance. White balance refers to the color of the light and assumes that the best light color is white. Some shots, like sunset or candlelight, do not have white light, but in general an impression of white light is desirable. Some use Photoshop's auto levels to set white balance, but that is not the best, since auto levels only sets the darkest areas to black and the brightest to white without considering 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 lightest pixels are rarely pure white).
When correcting white balance, the mid tones are the most important and in order to set the mid tones correctly one adds a grey card to the picture when taking the picture. A grey card is a sheet of cardboard or plastic colored 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 only include a gray card in the photo if one intends later to crop the photo.
If one does not want a gray card in the photo, or if one does not have a gray card , one can later use dedicated software that scans the image and finds the color of the light and sets it to white. There are problems with such software: what if there are no neutral areas in the photo to deduct the color of the light from? Some software does not need a neutral in the photo, but most do to get a good result.
If you work with RAW images, you will have found that the RAW converters usually come with a slider for color temperature, meaning a slider 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 neon light? The cool-warm slider is good for regular incandescent light, but not for fluorescent.
Color adjustment controls are rarely good for correcting white balance, because the color correction will not just neutralize the gray card, but will also tone the picture in an undesirable way: usually the blacks become toned or the whites or both. In short one needs some neutrals in an image to set white balance. A white wall or a sheet of white paper will do well; preferably add a gray card for the mid tones.
The first thing you might like to work on, when you begin to edit your images, is white balance. White balance refers to the color of the light and assumes that the best light color is white. Some shots, like sunset or candlelight, do not have white light, but in general an impression of white light is desirable. Some use Photoshop's auto levels to set white balance, but that is not the best, since auto levels only sets the darkest areas to black and the brightest to white without considering 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 lightest pixels are rarely pure white).
When correcting white balance, the mid tones are the most important and in order to set the mid tones correctly one adds a grey card to the picture when taking the picture. A grey card is a sheet of cardboard or plastic colored 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 only include a gray card in the photo if one intends later to crop the photo.
If one does not want a gray card in the photo, or if one does not have a gray card , one can later use dedicated software that scans the image and finds the color of the light and sets it to white. There are problems with such software: what if there are no neutral areas in the photo to deduct the color of the light from? Some software does not need a neutral in the photo, but most do to get a good result.
If you work with RAW images, you will have found that the RAW converters usually come with a slider for color temperature, meaning a slider 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 neon light? The cool-warm slider is good for regular incandescent light, but not for fluorescent.
Color adjustment controls are rarely good for correcting white balance, because the color correction will not just neutralize the gray card, but will also tone the picture in an undesirable way: usually the blacks become toned or the whites or both. In short one needs some neutrals in an image to set white balance. A white wall or a sheet of white paper will do well; preferably add a gray card for the mid tones.
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