Adobe photoshop cs2 사용자 설명서
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Chapter 11: Making color and tonal
adjustments
adjustments
Color and tonal corrections
Before making color and tonal adjustments
The powerful tools in Photoshop and ImageReady can enhance, repair, and correct the color and tonality (lightness,
darkness, and contrast) in an image. Here are some items to consider before making color and tonal adjustments.
darkness, and contrast) in an image. Here are some items to consider before making color and tonal adjustments.
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Work with a monitor that’s calibrated and profiled. For critical image editing, this is absolutely essential.
Otherwise, the image you see on your monitor will look different when printed.
Otherwise, the image you see on your monitor will look different when printed.
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Whenever you make a color or tonal adjustment to an image, some image information is discarded. It’s best to be
judicious regarding the amount of correction you apply to an image.
judicious regarding the amount of correction you apply to an image.
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(Photoshop) For critical work and maximum preservation of image data, it’s best if the image you work with is 16
bits per channel (16-bit image) rather than 8 bits per channel (8-bit image). Data is discarded when you make tonal
and color adjustments. The loss of image information is more critical in an 8-bit image than a 16-bit image.
Generally, 16-bit images have a larger file size than 8-bit images.
bits per channel (16-bit image) rather than 8 bits per channel (8-bit image). Data is discarded when you make tonal
and color adjustments. The loss of image information is more critical in an 8-bit image than a 16-bit image.
Generally, 16-bit images have a larger file size than 8-bit images.
Note: If you jump back and forth between Photoshop and ImageReady, be aware that ImageReady converts 16-bit images
to 8-bit for editing. After the images are saved in ImageReady, they are permanently converted to 8-bit images, and the
discarded data is unrecoverable. However, if you are editing a 16-bit image in ImageReady and haven't saved it yet, you
can return to Photoshop. Photoshop opens it as a 16-bit image without data loss.
to 8-bit for editing. After the images are saved in ImageReady, they are permanently converted to 8-bit images, and the
discarded data is unrecoverable. However, if you are editing a 16-bit image in ImageReady and haven't saved it yet, you
can return to Photoshop. Photoshop opens it as a 16-bit image without data loss.
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Duplicate or make a copy of the image file. Working on a copy of your image preserves the original in the event
you need to use the image in its original state.
you need to use the image in its original state.
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Remove any flaws such as dust spots, blemishes, and scratches from the image before making color and tonal
adjustments.
adjustments.
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(Photoshop) Plan to use adjustment layers to adjust the tonal range and color balance of your image rather than
applying an adjustment directly to the image layer itself. Adjustment layers let you go back and make successive
tonal adjustments without discarding data from the image layer. Keep in mind that using adjustment layers adds
to the file size of the image and demands more RAM from your computer.
applying an adjustment directly to the image layer itself. Adjustment layers let you go back and make successive
tonal adjustments without discarding data from the image layer. Keep in mind that using adjustment layers adds
to the file size of the image and demands more RAM from your computer.
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(Photoshop) Open the Info or Histogram palette in Expanded view. As you evaluate and correct the image, both
palettes display invaluable feedback on your adjustments.
palettes display invaluable feedback on your adjustments.
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You can make a selection or use a mask to confine your color and tonal adjustments to part of an image. Another
way to apply color and tonal adjustments selectively is to set up your document with image components on
different layers. Color and tonal adjustments are applied to only one layer at a time and affect only the image
components on the targeted layer.
way to apply color and tonal adjustments selectively is to set up your document with image components on
different layers. Color and tonal adjustments are applied to only one layer at a time and affect only the image
components on the targeted layer.