Справочник Пользователя для Adobe photoshop cs2
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ADOBE PHOTOSHOP CS2
User Guide
To specify the default interpolation method
1
Do one of the following:
•
In Windows, choose Edit > Preferences > General.
•
(Photoshop) In Mac OS choose Photoshop > Preferences > General.
•
(ImageReady) In Mac OS, choose ImageReady > Preferences > General.
2
For Interpolation, choose one of the following options:
Nearest Neighbor
A fast but less precise method that replicates the pixels in an image. This method is for use with
illustrations containing edges that are not anti-aliased, to preserve hard edges and produce a smaller file. However,
this method can produce jagged effects, which become apparent when you distort or scale an image or perform
multiple manipulations on a selection.
this method can produce jagged effects, which become apparent when you distort or scale an image or perform
multiple manipulations on a selection.
Bilinear
A method that adds pixels by averaging the color values of surrounding pixels. It produces medium-quality
results.
Bicubic
A slower but more precise method based on an examination of the values of surrounding pixels. Using more
complex calculations, Bicubic produces smoother tonal gradations than Nearest Neighbor or Bilinear.
Bicubic Smoother
A good method for enlarging images based on Bicubic interpolation but designed to produce
smoother results.
Bicubic Sharper
A good method for reducing the size of an image based on Bicubic interpolation with enhanced
sharpening. This method maintains the detail in a resampled image. If Bicubic Sharper oversharpens some areas of
an image, try using Bicubic.
an image, try using Bicubic.
To change the pixel dimensions of an image in Photoshop
When preparing images for online distribution, it’s useful to specify image size in terms of pixel dimensions.
Changing pixel dimensions affects not only the size of an image on-screen but also its image quality and its printed
characteristics—either its printed dimensions or its image resolution.
Changing pixel dimensions affects not only the size of an image on-screen but also its image quality and its printed
characteristics—either its printed dimensions or its image resolution.
1
Choose Image > Image Size.
2
To maintain the current ratio of pixel width to pixel height, select Constrain Proportions. This option automati
cally updates the width as you change the height, and vice versa.
3
Under Pixel Dimensions, enter values for Width and Height. To enter values as percentages of the current dimen
sions, choose Percent as the unit of measurement. The new file size for the image appears at the top of the Image Size
dialog box, with the old file size in parentheses.
dialog box, with the old file size in parentheses.
4
Make sure that Resample Image is selected, and choose an interpolation method.
5
If your image has layers with styles applied to them, select Scale Styles to scale the effects in the resized image. This
option is available only if you selected Constrain Proportions.
6
When you finish setting options, click OK.
For best results when you produce a smaller image, downsample and apply the Unsharp Mask filter. To produce a
larger image, rescan the image at a higher resolution.
larger image, rescan the image at a higher resolution.
To change the pixel dimensions of an image in ImageReady
1
Choose Image > Image Size.
2
To maintain the current ratio of pixel width to pixel height, select Constrain Proportions.