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Canon CS-S 4.3 User Manual

Page 60

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CONTENTS

GLOSSARY

INDEX

60

60

Chapter 5

Scanning Techniques

The following preview image has too dark a background, probably because
the photograph was exposed to set off the white flowers more effectively.

The histogram for this image shows that most of the pixels are between the
black and gray points, so there are too many dark pixels in the image. The
diagonal line indicates the color channel, in this case, the Master channel.

The following figure shows just the histogram of the same image, but with
the blue channel, the predominant color in the image, selected. Notice that
the blue pixels are more evenly spread around the midtones, but there is still a
large distribution of pixels in the dark-tone area.