To Skip Navigation Press Enter.Link to the Color Usage Site Home Page
Use the category links below to navigate this web site. All site pages can also be accessed with the site map.
Design Process Color Graphics Topics Color Tool Color Guidelines Aerospace
Color Science Utilities Site Map
Link back to the CURL Home Page

COLOR TOOL EXAMPLE: COLOR SPACE VISUALIZATION

One good use for the Color Tool is to get an overview of the perceptual organization of the colors available on a display. The "Choose by Hue" and "Choose by Lightness" color selection panels let us look at representative samples of all of the colors in the 3D gamut of a color display. The panels present two different planar slices through the 3D volume, displayed in perceptually-meaningful, uniformly-spaced coordinates. Users who don't have extensive training or experience with applied color perception (and maybe even a few who do have color training) can quickly see a few things about the visual possibilities supported by the display by browsing
More about 3D gamut of a display.

For example, the range of saturations in the display's gamut depends on both the hue and the lightness. To see the dependence on lightness, go to the "Choose by Lightness" color selection panel and click on 100, 90, 80, ..., 0 to view each page of hues and saturations. Not only does the maximum saturation (C*) on the page vary with lightness (L*), but the hue that has the maximum varies as well. At high L* the maximum C* is in the greens.

Color Tool Exmaple Image with lightness set to 80

At lower L* it shifts to the reds and blues.

Color Tool Exmaple Image with lightness set to 40

At the highest and lowest L* values none of the colors is very saturated.

Now select L* = 30 for the color selection panel and take a look at how background lightness influences the saturations. First select a high background L*, using the box on the left. Notice how this decreases the saturation of the darker colors. Now select a low background L*. The dark colors' saturations (and brightnesses) become much greater.

The "Choose by Hue" color selection panel is useful for revealing other aspects of the gamut. The pages for some hues (e.g., 5 deg) have "pointed" profiles, i.e., the maximum saturation falls off rapidly at lightnesses above and below the optimum.

Color Tool Exmaple Image showing the Choose by Hue feature and the background lightness settings

Others (e.g., 180 deg) have more "rounded" profiles. Maximum saturation is achieved over a range of lightnesses.

Color Tool Exmaple Image showing the Choose by Hue feature (hue set at 180 degrees) and the background lightness settings

This panel also allows inspection of the appearances of the available C* at a constant L* (rows) and the available L* at a constant C* (columns).

 


Related Topics:
go to this page
Color Tool



About This Site

Home
| Design Process | Color Graphics Topics | Color Tool | Guidelines | Aerospace | Color Science | Utilities

  Site Curator: Jeffrey McCandless | Responsible NASA Official: Jeffrey McCandless | Privacy Statement


NASA Logo     Ames Research Center Logo     Human Systems Integration Division Logo