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Stage 1 Compositing Images and Artwork
Technically speaking, compositing is the process of combining any two or more objects (images,
text, illustrations, etc.) into an overall design. When we talk about compositing in Photoshop, we’re
typically referring to the process of combining multiple images into a single cohesive
image. Image compositing might be as simple as placing two images into different Note:
areas of a background file; or it could be as complex as placing a person into a group The ad you’re building
photo, carefully clipping out the individual’s background, and adjusting the shadows in this project requires
to match the lighting in the group. compositing four digital
photographs. You will
Types of Images also incorporate title
There are two primary types of digital artwork: vector graphics and raster images. treatment and logo
Vector graphics are composed of mathematical descriptions of a series of lines files that were created
and shapes. Vector graphics are resolution independent; they can be freely enlarged in Adobe Illustrator
or reduced, and they are automatically output at the resolution of the output device. by other members of
The shapes that you create in Adobe InDesign, or in drawing applications such as your creative team. The
Adobe Illustrator, are vector graphics. various elements that
Raster images, such as photographs or files created in Adobe Photoshop, make up the ad are fairly
are made up of a grid of independent pixels (rasters or bits) in rows and columns representative of the type
(called a bitmap). Raster files are resolution dependent — their resolution is fixed, of work you can (and
determined when you scan, photograph, or otherwise create the file. You can typically probably will) create in
reduce raster images, but you cannot enlarge them without losing image quality. Photoshop.
Line art is a type of raster image that is made up entirely of 100% solid areas;
the pixels in a line-art image have only two options: they can be all black or all white.
Examples of line art are UPC bar codes or pen-and-ink drawings.
Screen Ruling
The ad that you will be building in this project is intended to be placed in print
magazines, so you have to build the new file with the appropriate settings for
commercial printing. When reproducing a photograph on a printing press, the Note:
image must be converted into a set of printable dots that fool the eye into believing Despite their origins
it sees continuous tones. Prior to image-editing software, pictures that were being in pre-digital print
prepared for printing on a press were photographed through a screen to create a grid workflows, these terms
of halftone dots. The result of this conversion is a halftone image; the dots used to persist in the digital
simulate continuous tone are called halftone dots. Light tones in a photograph are environment.
represented as small halftone dots; dark tones become large halftone dots.
The screens used to create the halftone
images had a finite number of available dots in
a horizontal or vertical inch. That number was
the screen ruling, or lines per inch (lpi) of the
halftone. A screen ruling of 133 lpi means that
in a square inch there are 133 1 133 (17,689)
possible locations for a halftone dot. If the screen
ruling is decreased, there are fewer total halftone
dots, producing a grainier image; if the screen
ruling is increased, there are more halftone dots,
producing a clearer image.
Line screen is a finite number based on a
combination of the intended output device and Each white square represents a pixel. The highlighted area shows the
paper. You can’t randomly select a line screen. pixel information used to generate a halftone dot. If an image only
Ask your printer what line screen will be used has 72 pixels per inch, the output device has to generate four halftone
before you begin creating your images. dots per pixel, resulting in poor printed quality.
Project 1: Composite Movie Ad 25

