Labs / Chapter 10
Chapter 10 reframes color as persuasion wrapped in hex codes. In this lab, you will turn color intent into a defensible palette specification that an LLM can generate, explain, critique, and revise.
Chapter 10 argues that color is not decoration. Color is the first argument a map makes. This lab teaches you to direct palettes through data logic, hue, value, saturation, accessibility, and rhetoric instead of letting an LLM choose colors by habit.
Choose one map scenario where color could easily mislead, overstate, or soften the message.
Map scenario Topic: Place: Audience: Data type: ordered / deviation from midpoint / categories Likely values or classes: Emotional tone the map should support: Interpretation the palette must avoid: Accessibility concerns: Cultural or political associations to handle carefully:
Ask an LLM to translate the scenario into color design requirements. Your goal is to separate hue, value, and saturation instead of asking for a vague “nice” palette.
Create a Color Literacy Brief for this map scenario. Explain how hue, value, and saturation should be used. Identify whether warm or cool colors should dominate, what should advance visually, what should recede, and which color associations could mislead the audience. Map scenario: [PASTE]
| Color property | Design decision | Reason | Risk if ignored |
|---|---|---|---|
| Hue | Example: Use a restrained blue ramp | Example: Matches the data logic | Example: Users may read a false pattern |
| Value | Example: Use a restrained blue ramp | Example: Matches the data logic | Example: Users may read a false pattern |
Starter examples only; expand this in your own notes or submission document.
Choose whether the map needs a sequential, diverging, or categorical scheme. Then make the LLM defend the choice.
Given this map scenario, identify the most appropriate color scheme type: sequential, diverging, or categorical. Explain why. Then explain what interpretive harm could occur if I used each of the other two scheme types instead. Return your answer as a decision memo with a final recommendation. Map scenario: [PASTE]
Generate three palettes for the same scenario. Each should include hex codes and a rationale. Do not accept a palette without an explanation.
Generate three candidate palettes for this map. Each palette must include 5-7 hex colors, a scheme type, a tone description, and a short explanation of hue, value, saturation, contrast, and possible cultural associations. Palette 1: neutral analytical Palette 2: urgent but not alarmist Palette 3: restrained and public-facing For each palette, explain what it makes users feel before reading the legend and what misunderstanding it might introduce. Map scenario and scheme decision: [PASTE]
| Palette | Hex colors | Rhetorical effect | Data fit | Risk |
|---|---|---|---|---|
| Neutral analytical | Example: Short note | Example: Changes what readers notice first | Example: Good fit if the data support it | Example: Could overstate certainty |
| Urgent but not alarmist | Example: Short note | Example: Changes what readers notice first | Example: Good fit if the data support it | Example: Could overstate certainty |
| Restrained public-facing | Example: Short note | Example: Changes what readers notice first | Example: Good fit if the data support it | Example: Could overstate certainty |
Starter examples only; expand this in your own notes or submission document.
Use the LLM as a palette critic. Ask it to look for legibility, color-vision issues, weak value contrast, and cultural assumptions.
Critique these palettes for accessibility and cultural interpretation. Evaluate: - likely distinguishability for common color-vision deficiencies - whether adjacent classes rely too much on hue instead of value - whether the palette has enough contrast for map symbols and labels - whether red, green, blue, black, white, or other colors carry audience-specific meanings - whether any palette implies danger, morality, prosperity, loss, cleanliness, disease, or political identity unintentionally - what redundant cue could support the palette if color alone fails Do not merely say the palettes are accessible. Give specific risks and revisions. Palettes: [PASTE]
Choose the strongest palette and revise it using concrete constraints. Keep the map’s tone intact while improving interpretability.
Revise the selected palette. Keep its intended rhetorical tone, but improve data logic, value contrast, color-vision robustness, and cultural sensitivity. Provide: 1. revised hex colors 2. what changed from the original palette 3. why each change improves the map 4. a note on labels, outlines, patterns, or symbol treatments that should support the palette 5. one risk that still remains Selected palette: [PASTE] Critique: [PASTE]
Turn the final palette into a reusable prompt that can guide a mapping agent or code assistant.
Write a production-ready color palette specification for this map. It must include: - map purpose and audience - scheme type and why it fits the data - emotional tone - hue, value, and saturation constraints - exact hex colors - accessibility requirements - cultural interpretation cautions - legend language that explains high/low or category meanings - fallback behavior if contrast fails - a self-check asking the assistant to justify the palette before using it Write this as a concise specification, not a general explanation.
Now make the contrast explicit. Ask the LLM to generate a bad or mismatched palette and explain why your specification is better.
Create one intentionally poor palette for this same map by choosing a mismatched scheme type, weak value contrast, or culturally misleading colors. Then compare it with my final palette specification. Explain the interpretive harm caused by the poor palette and the design protections built into my final specification.
Yes, we are doing this again. That is very much the point.
Do the tiny-but-mighty judgment check. If these answers are fuzzy, revise the map idea before polishing the prompt.
For use with Prompt Cartography: Interactive Web Map Design with LLMs, CRC Press. www.promptcartography.com
Prompt Cartography