| Course on Cartographic Techniques | Cartography Working Group | The Virtual Geography Department |
This module provides a thorough coverage of color theory principles and their practical application, It includes information on color formation, several color mixing systems, and methodologies for selecting color for various map data types. Lecture sessions incorporate lectures, classroom discussion, demonstrations and active-learning activities. In the exercises students will assess various color schemes, select and/or create colors, and apply color to selected thematic map types. Since computers and software are now available for producing color, the emphasis in lessons focuses on color selection decisions and computer color creation. Students of cartography, GIS and remote sensing (and web page design) will find the module lessons and exercises to be of great value as they often have difficulty in understanding the principles of color and how to apply these to creation of "appropriate" color. The exercises force students to critically read and evaluate the literature and examples on color as a map symbol, and to understand the importance of selecting appropriate colors for effective map/image design.
The instructor will need to insure that students have a solid grasp of color theory, as well as how to apply the theory to selecting appropriate color for use in map design and symbolization. Useful on and off-line sources of information include:
Preparation for this module will require that the instructor be familiar with color theory principles and their practical application to map design. The students will be expected to read the textbook and introductory on-line materials prior to the class and lab. The instructor should have many practical examples of color as is relevant to the particular lesson topic for use in class and lab, as such examples are difficult for students to obtain. The instructor will also need to insure internet access during class and lab times, and for after class use.
For the exercises, students may print the entire document from Netscape to use as reference while answering questions on the web forms. Students find is useful to jot down notes before entering their final answers. The hard copy notes also serve as a backup in case the student makes an error in submitting the file. Student printing will, however, monopolize the printers and use up printer paper. The instructor may therefore wish to print out one copy and make photocopies for the students to use. NOTE: You may wish to set the Page Setup (File, Page Setup) to Landscape Orientation in order to print the total width of all pages.
Some of the exercises involve the use of Adobe Illustrator or an equivalent graphics software. Instructions are provided for Adobe Illustrator. Normally the same functions can be performed on other software in a similar manner. Certain Adobe Illustrator tasks will be turned in to the instructor as a print or a digital file while related questions will be answered and submitted on the form. The color mixing and color in symbol design exercises make use of a Java Applet to create color. Students will create colors and write the percentages of cyan, magenta and yellow in the appropriate form spaces. The applet does not include black, therefore, where darker colors are needed, students may create color on Adobe Illustrator (or equivalent), or look to a color chart, then note down the percentages of cyan, magenta, yellow and black.
Lesson Procedures and Schedules:
This module is divided into four lessons where each lesson can span 30 minutes (or more) of lecture/demonstration/active learning activity and 1 to 1 1/2-hours of lab. Students will most likely need to do some of the work outside of class time, therefore, sufficient computer lab time will need to be available after class hours. The timing is set for a class that meets twice a week for 2 hours. Timing may need to be modified to suit a three 50-minute lecture course with associated lab time.
1. Lecture/Discussion: Provide an overview of the uses of color in mapping and stress the ways in which color improves map communication and visual appeal. Provide an outline of the introductory, theoretical topics to be discussed, and explain the importance of understanding the basic physical properties of color in order to apply them artistically to effective map design. Introduce students to the Electromagnetic Spectrum and point out that is the visible portion of the spectrum that is used in cartography. Relate the spectrum to the rainbow, noting that the order of color in the spectrum is the same as in the rainbow. Then introduce the concepts of additive and subtractive primary colors and how one set of primaries can be used to create the other. Make sure the students understand the difference between additive and subtractive color formation as this will be important for color mixing in Lesson 3.
2. Demonstration: The electromagnetic spectrum, the rainbow, absorbed and reflected color, and the additive and subtractive primaries can all be demonstrated in the Color Physics and Color Model components of the Interactive Color Module, provided a Macintosh computer is available. The module can be downloaded onto a Macintosh computer using the link to the module found in Lesson 1: Introduction to Color Theory. If using a PC or UNIX computer, the linked graphics and Java Applet found in Lesson 1 can be used to demonstrate these concepts as well. If available, set up a projection unit to project three additive or subtractive color filters to form the subtractive and additive primaries respectively.
3. Active Learning Activity: Have students use Adobe Illustrator (or equivalent graphics software) to mix the additive and subtractive primary colors. They may wish to work in groups of 2 or 3 and discuss their results. This will help them to understand how to create color using the software, and give them a start on their exercise.
1. Lecture/Discussion: This is a fun lesson, dealing with perceptual aspects of color that influence the map users ability to identify, differentiate, associate and understand color use on maps. Because each person sees and reacts to color a bit differently, it is impossible to list exact rules for perception and color. Instead, it is fun to explore the ways in which people react similarly or differently to color and how perceptual aspects are applied to the selection of color in map design and symbolization.
Begin by introducing the Color Dimensions of Hue, Value and Chroma. These components of color are an integral part of color for map symbol design and also for understanding how to mix colors. For perceptual aspects of color, start by covering color visual acuity and relate the effects of size of area and light source on the appearance of a given color. Color interactions is the next perceptual component to the lecture. Discuss and demonstrate the difference between simultaneous and successive contrast and how each is applied to color selection in mapping. Explore various color contrasts and show how certain color combinations can greatly improve the clarity and communication effectiveness of a map through good Figure-Ground. The third and final perceptual component is subjective reactions to color. Involve the students in a lively discussion of their own reactions to color in terms of preferred hues, color meanings or mood hues, impressions of advancing vs retreating colors, and color associations leading to the development of color conventions in mapping.
2. Demonstration: There are wonderful examples of the various perceptual aspects of color in the Perception, Attributes, Color Illusions and Harmony sections of the Interactive Color Module. If a Macintosh computer is available, these are highly recommended demonstrations of the principles covered in this lesson. The Lesson 2: Perceptual Aspects of Color portion of this module contains some good "static" examples, and in time a multimedia component to this module will be available on line with interactive exercises and examples of several perceptual aspects of color. A link to the Interactive Color Module is found in Lesson 2 as well. A few nice books on color combinations are: A Book of Colors, Shigenobu Kobayashi, Kodansha International, Tokyo, 1987, and Color Harmony: A Guide to Creative Color Combinations, Hideaki Chijiiwa, Rockport Publishers, Cincinnati,1988.
3. Active Learning Activity: Have the students experiment with the interactive exercises found in the Interactive Color module or the on-line multimedia component of this module. They can also experiment with various color combinations using Adobe Illustrator to prepare them for the exercise.
1. Lecture/Discussion: This lesson covers color mixing and color specification by 5 different color modeling systems. Flat and process color printing methods are introduced to help students understand how color is produced using these various systems. It is perhaps the most lengthy lesson and depending on the timing of a given course, it may be broken into two class periods. Begin by reviewing the Color Dimensions as they are mentioned as components of some of the specification systems. Make sure students understand that the purpose of color modeling or specification systems is to enable the consistent printing of color regardless of the computer system on which a map was created.
The 5 major color specification systems that are dealt with in the Cartography
textbooks are covered in this lesson: Munsell, CIE, Pantone, RGB, and one
of the Process Color Systems (there are several). The instructor
may wish to first review these systems in the textbooks and in the notes
on Lesson 3: Color Mixing; Production &
Printing of Color. Students should be required to read these materials
as well. The discussion of these systems can get lengthy and students may
lose focus. Therefore, it is recommended to break up the lecture with demonstrations
and active learning activities for each specification system. Again, depending
on the course structure, you may wish to divide the material into two sessions.
Finish by describing both Flat and Process Color Printing and relate
appropriate color specification systems to each printing method (e.g.,
Pantone for Flat, CMYK for Process).
2. Demonstration: As with the other lessons, the Interactive Color Module has some good demonstration material in the Color Model section. The material is not as interactive as in other sections but the graphics are excellent and the descriptions reinforce the graphics well. Lesson 3 contains some good diagrams as do the recommended textbooks. If possible, obtain a Munsell color solid, a Pantone book of color, a Process Color Chart, and any other color specification systems available (e.g., paint chips, color chips for soil identification, dental color specification for teeth, art or architecture color charts or books, etc.). Examples of as many systems as possible will reinforce the idea of consistency in color selection for final "production" or printing and will additionally demonstrate that color specification is used widely in many areas besides art and cartography.
Regarding the printing methods, obtain sample color proofs or printing negatives, positives, or plates to demonstrate the concept of color separation, and how different colors are printed on maps using each printing method. For process color separations, point out the use of screens to obtain percentages of CMYK, and demonstrate that many colors can be created from using only 4 printing inks.
3. Active Learning Activity: Students understand color mixing
best when they can create colors themselves. The following are some suggested
in class activities in color mixing:
Use Adobe Illustrator, or equivalent graphics software to mix colors
using CMYK and RGB. Adobe Illustrator has Pantone colors as well, though
they are already "mixed".
Bring white frosting and a food coloring set, cups, and spoons to class. Have students divide the frosting into cups and create a variety of colors using the 4 colors in the food coloring kit. There may be some suggested "recipes" for colors on the box, e.g., 1 drop red and 4 drops yellow makes orange. For a treat, bring in plain cookies or cupcakes that can be frosted with the colored frostings, then eaten.
Bring artists base paints or inks and paper plates and plastic knives or spoons to create a variety of colors with paint or ink. An art book on mixing paints or inks will indicate the proportions of various paints/inks to use to create specific colors. Try mixing with primary color inks vs other color inks. Try also to alter the value and chroma of each hue using black and white. A useful book is: The Book of Color by Jose M. Parramon, Watson-Guptill Publications, NY, 1993.
1. Lecture/Discussion: This lesson forms the final session in
the series on color theory. The emphasis of this lesson is to apply the
theory from the previous lessons to practical map symbol design. Begin
by exploring the many uses of color in map symbol design. This can be done
by looking at numerous examples of color maps. Comparison can be made with
black and white maps of similar symbol style (e.g., color line symbols
vs line symbols in black and white).
Actual symbol design is organized by measurement level of the data,
that is Qualitative and Quantitative. Start with strategies and examples
of color selection for representing nominal or qualitative data. Color
in this case should reflect contrast but not emphasis, thus colors of fairly
equal visual strength. Qualitative area maps often require many colors,
and it is difficult to achieve equal visual strength for much more than
10 colors. It is useful, therefore, to expose students to alternative solutions
such as pattern and letter overprints on same or similar colors, and using
darker colors in smaller areas and lighter ones in larger areas of a map.
Complete the lesson by discussing the uses of color to represent ordinal/interval,
or ranked/quantitative map data. Several hue series are covered in the
Dent and Robinson textbooks and can be reviewed and discussed in class.
The Dent book also looks in depth at 2 fairly recently established sets
of color schemes for quantitative data. These are developed by Drs. Jan
Mersey and Cindy Brewer. The Brewer series appears on-line as well, with
links from Lesson 4: Color in Symbol Design
and Exercise 4.
2. Demonstration: Several examples of qualitative and quantitative color are linked in Lesson 4: Color in Symbol Design. The link to Brewers Color Guidelines provides many examples of color for qualitative and quantitative, single and multi-variable data sets in map form. A description is provided for each classification within her color scheme. These graphics should prepare students well for Exercise 4.
3: Active Learning Activity: It is very difficult to create color series that are equal in visual strength, or hue series that have sufficient difference between each hue. It is helpful, therefore, for students to use Adobe Illustrator or equivalent graphic software to try and create several of the examples found in Lesson 4 and in Brewers Color Guidelines. Discuss their work with them and point out ways in which they can improve their color schemes.
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Created 2/20/98 by Laurie A. B. Garo. Last updated 5/28/99 by
lg.
The URL for this page is http://www.uncc.edu/lagaro/cwg/color/instructor.html