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发信人: killest (矛盾), 信区: Graphics
标  题: PHOTOSHOP(94)-Using Filters
发信站: 紫丁香 (Mon May  4 17:36:46 1998), 转信

Loading images and textures
Some filters let you load other images, such as tex-tures
and displacement maps, to use with a filter.
These filters include the Cont� Crayon, Displace,
Glass, Lighting Effects, Rough Pastels, Texture Fill,
Texturizer, Underpainting, and Custom filter dia-log
boxes. Not all these filters load images or tex-tures
in the same way; for information on the Dis-place
filter, see page 289; for information on
Lighting Effects, see page 291.
To load images and textures:
1 Choose the filter you want from the appropriate
filter submenu.
2 For Texture, choose Load Texture, and locate
and open a texture image. The texture must be in
the Photoshop format. If you choose a color file,
most filters will use only its grayscale information.
3 Click OK in the filter dialog box to apply the
settings.
Defining undistorted areas
The Displace, Shear, and Wave filters in the Distort
submenu, and the Offset filter in the Other sub-menu
let you choose the following ways to treat
areas undefined by the filter: Wrap Around copies the image to fill the unde-fined
space so that the area is filled with content
from the opposite side of the image. Repeat Edge Pixels extends the colors of the
pixels along the edge of the image in the direction
specified. Banding may result if the edge pixels are
different colors. Set to Background fills the selected area with the
current background color (available for the Offset
filter only).
Using texture and glass surface controls
Five filters included in Adobe Photoshop have tex-turizing
options梩he Cont� Crayon, Glass,
Rough Pastels, Texturizer, and Underpainting fil-ters.
The texturizing options can make an image
appear as though painted onto various textures,
such as canvas and brick, or viewed through glass
blocks.
To use texture and glass surface controls:
1 From the Filter menu, choose Artistic > Rough
Pastels, Artistic > Underpainting, Distort >Glass,
Sketch > Cont� Crayon, or Texture > Texturizer.
2 For Texture, choose a texture type or choose
Load Texture to specify a Photoshop file.
3 Drag the Scaling slider to enlarge or reduce the
effect on the image surface.
4 Drag the Relief slider (if available) to adjust the
depth of the texture抯 surface.
5 Select Invert to reverse the surface抯 light and
dark colors.
6 For Light Direction, indicate the direction of the
light source on the image.
283
7 Click OK.
Original Underpainting filter;
Canvas texture
Tips for creating special effects
Try the following techniques to create special
effects with filters.
Create edge effects When you apply an effect to
only a selected part of an image, you can use vari-ous
techniques to blend the effect into the original
image.
For a distinct edge, apply the filter effect as is, to
contrast it with the rest of the image. For a soft
edge, feather the edge and then apply a filter. For a
transparent effect, apply the filter, then use the
Fade command to adjust the selection抯 blending
mode and opacity. (See 揃lending filter effects� on
page 280 for more information.)
Distinct edge Feathered edge
Apply filters to layers Another way to vary filter
effects is by applying them to individual layers or
to several layers in succession to build up an effect.
For a filter to affect a layer, the layer must be visible
and it must contain pixels (for example, it could
contain a neutral fill color). For more information
about this option, see 揊illing a new layer with a
neutral color� on page 260.
Apply filters to individual channels For a special
effect, apply a filter to an individual channel of an
image, apply a different effect to each color chan-nel,
or apply the same filter but with different
settings.
Grayscale image converted to RGB
Graphic Pen filter applied to green and blue channels
Create backgrounds By applying effects to solid-color
or grayscale shapes, you can generate a
variety of backgrounds and textures. You can also
apply a texture, and then blur it. Try these filters to
create background texture: Add Noise, Chalk &
Charcoal, Clouds, Cont� Crayon, Craquelure, Dif-
CHAPTER 12 284
Using Filters
ference Clouds, Glass, Grain, Graphic Pen, Half-tone
Pattern, Mezzotint, Mosaic Tiles, Note Paper,
Patchwork, Pointillize, Reticulation, Rough Pas-tels,
Sponge, Stained Glass, Texture Fill, Texturizer,
and Underpainting. Note that some filters, such as
Glass, have little or no visible effect when applied
to a solid color.
Combine multiple effects with masks or with dupli-cate
images Use masks to combine multiple
effects. By using masks to create the selection
areas, you have more control over the transition
from one effect to another. For example, use a
mask to create a selection, and then filter the selec-tion.
Or create a smoother transition by creating a
mask of the entire image, and then filling it with a
black-to-white gradient fill. Paste it into the first
copy of the original.
Mask with gradient fill
Water Paper and Rough Pastels applied
through mask
Use two duplicate images to apply various effects
to selected areas in each image, and then recom-bine
the two images. For example, apply a different
effect to each of two copies of an image, and then
use the Clone option of the rubber stamp tool to
paint one copy onto the other copy.
Improve image consistency If you抮e working with a
series of photos of varying or poor quality, you can
achieve a unified look in the final piece by applying
the same effect to each image to disguise the faults
of the original or to alter or enhance the mode of
the image. Use the Actions palette to record and
preserve the process you use to modify one image,
then play back the action to other images. For
more information, see Chapter 15, 揂utomating
Tasks.�
Original too dark
Chalk and Charcoal filter applied

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