We describe a spatial extension to the CIELAB color metric that is useful for. Plement S-CIELAB as a pre-processor to existing CIELAB-related software.
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Freeware, source codes, ICC profiles, pdf files, … here you can find miscellaneous colour-related software.
CIELAB HLC Colour Atlas (XL)
Our own premium product: The CIELAB HLC Colour Atlas developed according to DIN SPEC 16699 is the new basis for all stages of professional colour communication – from design to the finished product, even with exact colour formulation.
HLC Colour Atlas
Standard version with 2040 colours: The CIELAB colour space is run through in 10 unit steps for H/L/C on 36 pages; includes the most important gamuts, sRGB/CMYK colour values, spectral data, ase file
Version 2.3 as of 2018-02-12 (5.7 MB): HLC-Colour-Atlas_EPV_v2-3en_Set.zip
SHA-256 check sum: 1a2c32b52f8659964de5fe8e9a98da17074fe756c821704a24367a69f5b30775
HLC Colour Atlas XL
Large version with 13283 colours: The CIELAB colour space is traversed in 5 unit steps for H/L/C on 72 pages; includes the most important gamuts, sRGB/CMYK colour values, and spectral data
Version 1.2 as of 2019-01-30 (18.5 MB): HLC-Colour-Atlas-XL_Set_DE_v1-2.zip
SHA-256 check sum: 49d0bc10aeb90ee4b6f30d20305dd919caa37eca94e81a80ebf8e23b36ed1bdd
The components in detail:
The ring binder versions produced in highly accurate proof printing can be ordered from proof GmbH, CCVision and grafipress. State-of-the-art inkjet technology reproduced all colours in the measured master copy with an accuracy of DeltaE00<1 (average DeltaE00=0.5) – a printing accuracy that was unthinkable just a few years ago.
Freeware
Palettes
Practical tools
Colour range overview
Open Colour Systems Collection (OCSC)
Over 370 colour systems for use in graphic, design or CAD applications. The version 2.0 contains (depending on target software) RGB or Lab colour values. In addition there are plain text files and photos of the fans – for free use and free distribution under a Creative Commons license.
Colour conversion with Excel / VBA
Sourcecodes
![]() ICC Profiles
Here are the most important ICC profiles, which are used in practice.
Your Download
Do you have any interesting material on the subject, or have you created something you would like to share?
Send us a short description – we would be happy to put it here. 243 Chapter 11 ∣ Color Copyright Goodheart-Willcox Co., Inc. formed by this curve. Connecting the spectrum locus curve endpoints forms a line called the purple line, or the purple boundary. Colors on this line are mixtures of pure violet (380 nm) and red (770 nm) light, Figure 11-19B. The colors plotted on the chromaticity diagram are relative to the light source used. The A, C, D 50 , and D 65 labels in Figure 11-19A represent the location of the CIE standard light sources. The CIE values of dominant wavelength, purity, and luminosity are dependent on the color temperature of the light source used in making the measurements. In the CIE system, dominant wavelength relates to hue, and purity relates to chroma or saturation. CIELAB In 1976, the CIE revised the standards to create a more even distribution of colors. The result is the CIELAB model, Figure 11-20. The distance between colors corresponds to perceived color differences. The CIELAB model is the current standard for measuring the color of light and is very similar to Munsell’s color model. The CIELAB color space separates color and luminance into discrete color space dimensions. These dimensions are represented by the designations L, A, and B. • L. The first dimension, which represents lightness. All colors of the same lightness lie in a plane. Lightness varies vertically. • A. Indicates the red to green value. Positive a* values (+a*) appear reddish and negative a* values (–a*) appear greenish. • B. Represents the yellow to blue value. Positive b* values (+b*) are yellowish and negative b* values (–b*) are bluish. The a* and b* designations both represent a two- dimensional color subspace. The human visual system is more sensitive to the L dimension, so digital systems allocate more data space to it than to the color components. This allows even more efficient coding of the color values. Using the LAB color gamut is the only true way to accurately describe color that is device- independent. The Pantone® System The Pantone system of color specification is widely used in the graphic communications industry. Unlike the HVC or HSB color models, the Pantone system is not based on equal visual differences in color. The colors used are based on ink colors common to the printing industry. Manuals and swatchbooks provide Pantone color representations, names, and mixing formulas, Figure 11-21. The colors are usually presented on both coated and uncoated paper. Using the manuals or swatchbooks, designers, clients, and printers can effectively communicate color selections. The swatchbooks and the accuracy of their color depend on the paper, the press, and the age of the book itself. For years, displaying the Pantone inks on your monitor and printing to your desktop printer were unreliable ways to represent the inks. The libraries in the software programs that defined the colors used different lookup tables, all in CMYK format, which made proofing inconsistent. The newer Pantone Plus series has changed how they define the colors. Using LAB values to define the colors, these spot colors provide a more accurate representation of the actual Pantone inks, and are consistent throughout applications and devices, including desktop and mobile. It is important to make sure you have properly communicated with all parties involved in a project when using Pantone colors. Goodheart-Willcox Publisher Figure 11-20. The CIELAB color space defines color based on our visual system’s perception of color. ![]() Comments are closed.
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