The Essential Guide to User Interface Design

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The Essential Guide to User Interface Design - 3rd Edition
Wilbert O. Galitz
TEST ANSWERS
Step 12: Choose the Proper Colors
Short Answer
1. What is the percentage of people possess a color-viewing deficiency?
Males—8 percent.
Females—0.4 percent.
2. What four ways can color can be used in design?
Assist in formatting a screen:
As a visual code.
Realistically portray natural objects.
Increase screen appeal.
3. What are the warm colors and how should they be used in design?
o Red
o Orange
o Yellow
To indicate that actions are necessary.
4. When text is changed from black to a color, what must be done to the text?
Use bolder or larger type.
o If originally 8 to 12 points, increase by 1 to 2 points.
o If originally 14 to 24 points, increase by 2 to 4 points.
5. What are some possible problems that may be encountered in using color on
screens?
When used improperly, color may even impair performance by
distracting the viewer and interfering with the handling of information.
High attention-getting capacity—Color has an extremely high
attention-getting capacity. This quality causes the screen viewer
to associate, or tie together, screen elements of the same color,
whether or not such an association should be made.
Interference with use of other screens—Indiscriminate or poor use of
color on some screens will diminish the effectiveness of color on
other screens. The rationale for color will be difficult to
understand and its attention-getting capacity severely restricted.
Varying sensitivity of the eye to different colors—All colors are not
equal in the eye of the viewer. The eye is more sensitive to those
in the middle of the visual spectrum (yellow and green), which
appear brighter than those at the extremes (blue and red). Thus,
text composed of colors at the extremes is thought to be more
difficult to read.
Color-viewing deficiencies—About 8 percent of males and 0.4 percent
of females have some form of color-perception deficiency- color
blindness, as it is commonly called.
Color connotations—Colors have developed certain meanings to people
in certain situations, either personally in a discipline or in a
culture. A color used in an unexpected way can cause confusion.
6. Why is an emergency vehicle, such as a fire truck, often painted yellow or
chartreuse?
These colors are maximally sensitive for peripheral viewing because the
periphery of the retina is most sensitive to these colors.
7. What are the cool colors and how should they be used in design?
o Green
o Blue
o Violet
o Purple
To provide status or background information, use cool colors.
8. What does ROY G BIV refer to?
The spectral positioning of colors (red, orange, yellow, green, blue,
indigo, violet).
9. On a textual screen, what is the recommended maximum number of
different colors that should be displayed at one time?
Four. While not experimentally verified, experience indicates that
displaying more than four colors at one time on a textual screen gives
rise to a feeling of “too much.”
10. The wavelength of light creating what color can never be brought into focus
on the retina but is always focused in front of it.
Blue. A sharp blue image is impossible to obtain.
True/False (Answers highlighted and underlined)
1. The eye is equally sensitive to all colors of the visual spectrum.
True or False?
2. The size of a colored image, the color of images adjacent to it, and t he
ambient illumination all exert an influence on what color is actually
perceived by the user.
True or False?
3. A color used in an unexpected way can cause user confusion.
True or False?
4. Poor use of color is worse than not using it at all.
True or False?
5. The different wavelengths of light themselves are colored.
True or False?
6. Color can be used to render a statistical graphic screen more legible and
meaningful.
True or False?
7. On Web pages, make selected/visited links pink.
True or False?
8. On Web pages, larger images should use fewer colors than small images.
True or False?
9. Color is always more important than Web page content.
True or False?
10. Too many colors at one time may make a screen confusing or unpleasant to
look at. Use only enough color to fulfill the system’s objectives.
True or False?
Multiple Choice (Answers highlighted and underlined)
1. Which of the following guidelines are correct?
a) Blue is very effective used for peripheral viewing.
b) Blue is very effective in the center of the visual field.
c) Green is very effective used for peripheral viewing.
d) Green is very effective in the center of the visual field.
e) Red is very effective used for peripheral viewing.
f) Red is very effective in the center of the visual field.
g) Yellow is very effective used for peripheral viewing.
h) Yellow is very effective in the center of the visual field.
i) All of the above.
2. For best absolute discrimination and identification of a color, what is the
maximum number that should be used together?
a) 1
b) 2–3
c) 4–5
d) 6–7
e) It does not matter.
3. Which of the following statements about human vision are correct?
a) The wavelengths of light that create different colors are focused
at different distances behind the lens.
b) The shorter wavelengths (blue) are focused farther back than the
longer wavelengths (red).
c) The wavelength of light that creates blues can never be brought
into focus on the retina but is always focused in front of it.
d) The lens transmits all light wavelengths equally.
e) Adaptation to increases in brightness improves color sensitivity.
Color adaptation “softens” colors.
f) All cones are equally sensitive to all colors.
4.
5.
6.
7.
8.
g) A clear, sharp image requires a difference in brightness between
adjacent objects, as well as differences in color.
h) The eye is most sensitive to colors at the extreme of the visual
spectrum and less sensitive to colors in the middle.
i) All the above.
Which of the following statements about using color are correct?
a) Use colors conservatively.
b) Very pure or saturated colors require more eye refocusing than
less pure or unsaturated colors.
c) Use pure blue for text, thin lines, and small shapes.
d) Never use color as a redundant screen code.
e) For extended viewing or older viewers, use brighter colors.
f) To convey similarity, use similar colors.
g) All of the above.
Which of the following statements about color connotations are correct?
a) People’s tastes in color are generally the same within a culture.
b) Differences in color connotations exist between cultures.
c) Connotations may be due to color associations learned in
childhood.
d) A color used in an unexpected way usually causes no problems.
e) The proper use of color requires an analysis of the expectations
and experiences of the screen viewer.
d) All of the above.
For people with color-viewing deficiencies, which of the following
guidelines are correct?
a) Use color combinations that can be easily discriminated.
b) Ensure that the lightness contrast between foreground colors is high.
c) Increase the lightness contrast between colors on either end of the
visual spectrum (blues and reds).
d) Avoid combining light colors from either end of the spectrum with
dark colors from the middle of the spectrum.
e) Use tools to see what screens or pages will look like to color deficient
viewers.
f) All of the above.
For colored backgrounds, which of the following guidelines are correct?
a) Use a background color to organize a group of elements into a
unified whole.
b) Use colors that do not compete with the foreground.
c) Use colors from the middle of the spectrum.
d) Use light-colored backgrounds of low intensity: Off-white or light
gray.
e) Use cool, dark colors such as blue or black.
f) Use saturated colors.
g) All of the above.
Which of the following statements about what to avoid in using color are
correct?
a) Avoid highly saturated, spectrally extreme colors together.
b) Avoid high-brightness colors for extended viewing or older viewers.
c) Avoid colors of equal brightness.
d) Avoid fully saturated colors for text or other frequently read
screen components.
e) Avoid colors in large areas.
f) Avoid color for fine details.
g) Avoid using blue or yellow in the periphery of displays.
h) Avoid using colors in unexpected ways.
i) Avoid using color to improve legibility of densely packed text.
9. Which of the following statements about using color are correct?
a) For best comparative discrimination, select no more than six or
seven colors widely spaced on the color spectrum.
b) To draw attention or to emphasize elements, use bright or
highlighted colors.
c) Order colors by their spectral position.
d) Provide a default set of colors for all screen components.
e) For fine discriminations use a color scale.
f) A color with a large white component will require less eye
refocusing.
g) A sharp blue image is easy for the eye to obtain.
h) All of the above.
10. Which of the following statements about using color are correct?
a) Choose harmonious colors.
b) To indicate that actions are necessary, use cool colors.
c) To de-emphasize elements, use less bright colors.
d) Use foregrounds colors that highly contrast with the background
color.
e) When switching text from black to color the width of lines need not
be changed.
f) Check color legibility by squinting at text. Too-light type will
recede or even disappear.
g) Sharp contrasts in brightness in things being viewed can lead to
visual fatigue as the eye continually makes muscular adjustments.
h) All of the above.
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