A Color Vision Deficiency learning tool by Germán Cerrato, Creator of the Inclusive Color System.
Value family
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Select a circle to inspect it. Double-click a circle to enlarge it below.
Enlarged color view
Nopia™ Creative Vision Tool
NopiaLens™
Explore Color Through a Different Lens. Upload an image, compare the original with an educational CVD simulation, and save the transformed image for classroom, studio, or personal learning use.
REFERENCE
Original Image
NOPIALENS™ VIEW
Original
Controlled color check
12-Hue Reference Strip
Light, base, and dark samples make it easier to observe how hue relationships change in the selected simulation.
Original
Original
About the simulation
NopiaLens™ provides educational approximations of Protanopia, Deuteranopia, Tritanopia, and Achromatopsia. Individual color perception can vary, and display settings, lighting, and surrounding colors can affect appearance. NopiaLens™ is an educational and creative color-reference tool, not a medical diagnostic test.
Methodology: The Protanopia, Deuteranopia, and Tritanopia transformations use full-severity color-vision-deficiency matrices based on published work by Machado, Oliveira, and Fernandes. Achromatopsia is represented with luminance-based grayscale.
Privacy: Images selected with Upload Your Image are processed locally in your browser by this tool; NopiaLens™ does not intentionally upload them to a server.
Nopia combines an interactive color wheel, permanent color names, Nopia Codes, value families, and digital color references so a user can identify and explore a color through more than appearance alone.
Use Protanopia, Deuteranopia, Tritanopia, or Achromatopsia to move into the corresponding Nopia palette.
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Explore the color wheel
The wheel is the visual map. Select a hue family by its button or by the interactive core-color areas on the wheel.
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Select a hue family
The twelve hue-family controls organize the chromatic palettes and connect the wheel to the permanent Nopia registry.
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Explore darker and lighter values
Each family displays its named value progression below the wheel. The permanent name is written above its color circle. Select any circle to inspect that exact registry color.
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Read the information panel
The right panel follows the selected color and displays its permanent name, condition, Nopia Code, HEX/RGB, hue family, value position, and available color relationships.
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Enlarge the color
Double-click a value circle on desktop, or use Enlarge selected color, to isolate the color in a larger viewing area.
Understanding the Nopia Color System
The app keeps each CVD condition as its own organized palette. Within the chromatic conditions, a hue family contains a Core color together with darker and lighter values. Permanent names and Nopia Codes give each registry entry an identity that can be referenced alongside HEX and RGB.
Important: Nopia is a structured educational and color-reference system. It does not claim that every person with the same CVD condition experiences a color identically.
Reading a Nopia color
Permanent Name→CVD Condition→Nopia Code→HEX / RGB→Hue Family→Value Position
These identifiers work together. The name makes the color easier to discuss, the code provides a precise Nopia reference, HEX/RGB identifies the digital color, and hue/value information locates it within the system.
The Nopia Naming System
The permanent names are part of the Nopia registry rather than temporary labels. The Core name identifies the central member of a hue family, while the darker and lighter names distinguish the surrounding values. Keeping the names outside the circles preserves readability even when the swatch itself is very dark or very light.
Understanding CVD
Why the four Nopia conditions differ
Color vision depends on cone photoreceptors in the retina. Three cone classes are commonly described by the wavelength ranges to which their photopigments are most sensitive: L (long), M (middle), and S (short). Differences in cone or photopigment function can change how colors are distinguished.
Protanopia
A red-green color vision deficiency associated with absent L-cone function. This changes discrimination among colors that normally depend strongly on long-wavelength cone information.
Deuteranopia
A red-green color vision deficiency associated with absent M-cone function. It also affects distinctions in the red-green range, but its cone-function basis differs from Protanopia.
Tritanopia
A blue-yellow color vision deficiency associated with absent or severely impaired S-cone function. Blue-green and some yellow-related distinctions can become difficult.
Achromatopsia
A distinct disorder involving impaired cone function. Complete achromatopsia can result in an absence of color perception, with vision described in black, white, and shades of gray.
Why Nopia separates the conditions
Because the underlying color-vision differences are not the same, Nopia keeps Protanopia, Deuteranopia, Tritanopia, and Achromatopsia as separate learning palettes instead of treating CVD as one universal appearance.
Color Perception Notice
Color perception varies among individuals. The colors presented in the Nopia™ system may not appear identical to every viewer, including people who share the same general type of color vision deficiency. Screen characteristics, display settings, lighting, surrounding colors, and other viewing conditions may also affect perceived appearance.
Nopia™ colors, names, codes, and palettes are provided as a structured educational and color-reference system and should not be interpreted as representing an identical visual experience for every individual.
Educational references for this page
The general CVD and cone-function explanations are based on public educational information from the U.S. National Eye Institute and NIH MedlinePlus. Nopia palette names, codes, values, and organization remain based on the Nopia Master Registry.
Nopia is designed as a learning and reference environment in which users can explore organized CVD palettes, identify colors consistently, and carry those references into educational and creative work.
Purpose & applications
Education
Use names, codes, hue families, and value progressions as additional ways to discuss color in lessons and demonstrations.
Art & design exploration
Use the palettes as references for studying combinations, value movement, and intentional color choices.
Color communication
Use a permanent Nopia name and code alongside HEX/RGB so a color can be referenced without depending on appearance alone.
Artwork & Color Applications
Planned expansion
A future section will present artwork examples and practical ideas for using Nopia palettes. This area is intentionally reserved so the educational app can grow without complicating the interactive wheel.
About the Inclusive Color System
Nopia™ is presented as part of the Inclusive Color System created by Germán Cerrato. The system brings together structured methods of color identification, organization, and education with an emphasis on making color information easier to communicate and explore.
Nopia™ and the Inclusive Color System™, including their proprietary naming system, Nopia Codes, organized color palettes, graphics, artwork, educational content, and application materials, are presented as intellectual property of Germán Cerrato / Color Theory Education, LLC.
Access through a paid membership grants the authorized member a limited license to use the Nopia™ system for personal, educational, and authorized instructional purposes. Membership does not grant permission to reproduce, redistribute, publish, sublicense, sell, commercially exploit, or incorporate proprietary Nopia™ materials into commercial products or services without prior written permission from the copyright owner.
This in-app notice is a project usage statement and is not a substitute for a lawyer-reviewed license agreement.
