Graphics Programs Reference
In-Depth Information
4
Sizing Digital
Images
Once you've acquired your digital images, you'll need to size them
for your project (as well as ultimate output). For many Photoshop
users, such as photographers, this may be as straightforward as
cropping and sizing. This chapter explores several techniques for
sizing your images. You'll learn about the concept of resampling,
which addresses how the computer adds or subtracts information
from a digital image while trying to retain detail and clarity.
Resolution
Revisited
Chapter 3 looked closely at the
process of acquiring digital
images. If you skipped ahead
or just skimmed that chapter,
go back—a solid understanding
of those concepts is required to
move forward. Quite simply,
you must know the capabilities
of your digital camera or scan-
ner to process information.
Previous chapters also briefly
discussed resolution require-
ments for different output
formats. The second part of the
image-sizing puzzle is a clear
understanding of these output
requirements. What resolution does your printer need? Are you
sending the image to a service provider such as a commercial
This photo was scanned at two different resolutions. The image on the left was
scanned at 300 spi, and the image on the right was scanned at 72 spi. Examine
the detailed enlargements to see the impact of different scanner settings.
