Adobe photoshop elements Manual Do Utilizador
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Chapter 2: Getting Images into
Photoshop Elements
Photoshop Elements
ou can get digital images from a variety of
sources—you can create new images,
import them from another graphics appli-
sources—you can create new images,
import them from another graphics appli-
cation, or capture them using a digital camera.
Often you will begin by scanning a photograph,
a slide, or an image. To create effective artwork,
you must understand some basic concepts about
how to work with digital images, how to produce
high-quality scans, how to work with a variety of
file formats, and how to adjust the resolution and
size of images.
Often you will begin by scanning a photograph,
a slide, or an image. To create effective artwork,
you must understand some basic concepts about
how to work with digital images, how to produce
high-quality scans, how to work with a variety of
file formats, and how to adjust the resolution and
size of images.
About bitmap images and vector
graphics
graphics
Computer graphics falls into two main
categories—bitmap and vector. You can work with
both types of graphics in Photoshop Elements;
moreover, a Photoshop Elements file can contain
both bitmap and vector data. Understanding the
difference between the two categories helps as you
create, edit, and import artwork.
categories—bitmap and vector. You can work with
both types of graphics in Photoshop Elements;
moreover, a Photoshop Elements file can contain
both bitmap and vector data. Understanding the
difference between the two categories helps as you
create, edit, and import artwork.
Bitmap images
Bitmap images—technically
called raster images—use a grid of colors known as
pixels to represent images. Each pixel is assigned a
specific location and color value. For example,
a bicycle tire in a bitmap image is made up of a
mosaic of pixels in that location. When working
with bitmap images, you edit pixels rather than
objects or shapes.
pixels to represent images. Each pixel is assigned a
specific location and color value. For example,
a bicycle tire in a bitmap image is made up of a
mosaic of pixels in that location. When working
with bitmap images, you edit pixels rather than
objects or shapes.
Bitmap images are the most common electronic
medium for continuous-tone images, such as
photographs or digital paintings, because they can
represent subtle gradations of shades and color.
Bitmap images are resolution-dependent—that is,
they contain a fixed number of pixels. As a result,
they can lose detail and appear jagged if they are
scaled on-screen or if they are printed at a lower
resolution than they were created for.
medium for continuous-tone images, such as
photographs or digital paintings, because they can
represent subtle gradations of shades and color.
Bitmap images are resolution-dependent—that is,
they contain a fixed number of pixels. As a result,
they can lose detail and appear jagged if they are
scaled on-screen or if they are printed at a lower
resolution than they were created for.
Note: Bitmap images in Photoshop Elements are not
the same as images saved using the .bmp file format
in Windows.
the same as images saved using the .bmp file format
in Windows.
Bitmap images are good for reproducing subtle gradations
of color, as in photographs. They can have jagged edges
when printed at too large a size or displayed at too high a
magnification.
of color, as in photographs. They can have jagged edges
when printed at too large a size or displayed at too high a
magnification.
Vector graphics
Vector graphics are made up of
lines and curves defined by mathematical objects
called vectors. Vectors describe an image according
to its geometric characteristics. For example, a
bicycle tire in a vector graphic is made up of a
mathematical definition of a circle drawn with a
called vectors. Vectors describe an image according
to its geometric characteristics. For example, a
bicycle tire in a vector graphic is made up of a
mathematical definition of a circle drawn with a
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