How we measure and use color

Measurements taken from our masstone swatches or a painted chart (with CIE Standard Illuminant D50 "warm daylight" 5000K)

Lascaux Gouache

Brand colors on color planes

Example of a brand's range of colors on different color planes (Oklab, CIECAM02, CIECAM16, CIELAB)
Click on the magnifier to see a full sized version with
  • more color planes (the above + Munsell)
  • filtering for lightness (value scale)
  • 3D view
  • comparision options (for other brands and your collections)

Everything we can think of...

Art material

What you see on our website as a representation of a brand's color "Gradient swatch" and also our "Masstone swatch" which is the basis of color measurement and color plane visualisation, is a one-time sampling.

  • We cannot be sure that all brands keep all their colors consistent over time (between batches or on the long run).
  • Storage can affect the conditon of tube colors, and color can be affected by how much binder is in the sample.
  • The same color can look different or behave differently if it comes from the tube / pan / dot card.


Paper can affect color with its

  • Own color (especially when used with more transparent mediums)
  • Texture (how it accepts color and reflects light)
  • Thickness / Structure (how it lets through light to the surface below when measuring)

We use natural white paper with no optical brighteners, suitable for the mediums.

Read more about our papers at "How our color samples are made (masstone)"

Sample / Application of art material on paper

How one uses art materials can be very unique to that person.

With our masstone samples, we need to make them as opaque and even as possible with normal use of the medium on quality paper. We use different papers, tools and techniques suitable for the medium and try to be consistent.

  • All these differences matter more in the case of certain mediums and colors.
  • Masstone can be dramatically different from how one usually thinks of a color (it's typical hue and lightness) or its undertone.

Most of our samples are our hand made masstone swatches.

Some exceptions are mediums which wouldn't be available for us for sampling and we decided to use their painted color charts as source.

Read more about our masstone swatches at "How our color samples are made (masstone)"


Color sensor devices can simulate different observation and lighting conditions, so it's important to know what observer and illuminant was used for the color measuring to be able to interpret the results.

Measurement modes can also vary and define how much of the UV spectra is contained and can even compensate for optical brighteners.

Specs include

  • Light source
  • Illuminants
  • Observers
  • Spectral range
  • Measurement geometry
  • Measurement aperture
  • Measurement modes

Devices have different accuracy and precision (Inter-Instrument Agreement and Repeatability) and they usually offer white tile calibration, which is essential.

Read more about our devices at "How we measure colors (devices)"


  • Temperature can affect certain mediums and extremities could affect measuring devices too.
  • Surface color and texture beneath the sample can affect measuring.
  • Uneven and transparent samples will be more affected by paper color etc. and the exact spot of measuring.

Our color data is measured on masstone swatches (made as opaque as possible with normal use of the medium and the specific brand on quality paper). You can find these samples on the individual pages of brand colors.

Papers used

  • Hahnemühle Echt-Bütten Aquarellkarton "50x65 cm" 300gsm (for watercolors)
    natural white
    L: 96.19,
    a: 0.25,
    b: 2.87
  • Fabriano Accademia Drawing & Watercolour Natural grain "Maxi block" 240gsm (for gouache and acrylics)
    L: 96.65,
    a: 0.43,
    b: 1.60
  • Daler Rowney Simply Drawing 120gsm (for colored pencils)
    L: 95.94,
    a: 0.89,
    b: 0.87
  • Hahnemühle Skizze/Pastel 130gsm 100% cotton (for pastels and oil pastels)
    natural white
    L: 96.48,
    a: 0.77,
    b: 1.57


  • For watercolor and ink, we use a brush to paint a concentrated, full-strength sample. (Dry pigments are also made into watercolors with a store-bought watercolor medium.)
  • For gouache and acrylic, we use a palette knife to paint a tube color sample.
  • For colored pencils, we use medium pressure for shading, and aim for a good even coverage.
  • For dry pastels, we don't use any special tools, just the art material itself (and how much the paper can comfortably take).
  • For oil pastels, we occasionally use a palette knife when the surface needs to be evened out.

Currently we only have dry masstone samples for water-soluble mediums like water-soluble colored pencil or pastel.

Read about color sensor devices →

Devices we have used

  • NCS Colourpin Pro (Nov. 2022 - March 2023)
    For our first experiments with color measuring and visualization on color planes. (Top entry-level device "Color reader" no spectral data)
  • Nix Spectro 2 (March - Dec. 2023)
    For our experiments with digital color mixing and providing spectral curves with our color data. (Top entry-level device "Spectrophotometer" with spectral data)
  • X-Rite i1Basic Pro 3 (2024 -)
    For an improved workflow (measurement time, software), spectral range 380-730 nm, multi-purpose light measurements. (Affordable professional-level device)

Measurements with Nix Spectro 2 and X-rite i1Basic Pro3 give very similar results.

We still need to redo some measuring for about 1000 swatches / colors (mostly our colored pencil masstones) measured with NCS Colourpin Pro which gives visibly different results.

Settings we use

  • Illuminant D50
  • Observer 2°
  • Measurement mode M2 with our Nix and M1 with our X-Rite device.

We use the following algorithms and software components

For swatches uploaded after 2022.12.01 I use the following setup:

  • I scan the images with an Epson V600 scanner in Silverfast SE Studio 9, the only software I've found which can save files in ProPhoto RGB color space (Epson's own MacOS software - Epson Scan 2 - can only create 8-bit files in Adobe RGB color space at best).
  • For slicing the images I use Adobe Lightroom Classic / Photoshop, and keep the color space as ProPhoto RGB throughout the process.
  • I export the images to sRGB JPEGs and Display P3 PNGs. Depending on your monitor, operating system, and your browser, you may get different images.

See also color support in browsers →

The sRGB (standard RGB) color space was created back in 1996, and it's still the default color space for the web. Although most of the modern monitors and mobile displays are capable of displaying wider gamut than the sRGB can offer, web developers are still using the sRGB color space to define colors.

See also color support in browsers →

When processing swatches, I export images to sRGB JPEGs and Display P3 PNGs. Depending on your monitor, operating system, and your browser, you see the best possible format.

Display P3 PNG
Display P3 PNG

Here are two examples: The same scans, exported to sRGB color space and Display P3 color space (on the right). The only difference is the color space, the images are the same, no other modification.

The data sources for the color navigators are:

There are some other great sources available for color notations for artist materials:

  1. Watercolors: CIE L*a*b* and CIECAM02 values for watercolors are available on
  2. Oil: A Munsell explorer is available on
  3. Pastels: Almost 3000 Munsell notations for pastels are available on Paul Centore's An Artist's Guide to Pastel colors page.
  4. Different mediums: Multiple artist brand's CIE readings available on freiFarbe under `Open color Systems Collection (OCSC) 2.0`.
  5. Different mediums: Color Mixing Tools contains measured data for many paint lines.

For some (mostly Japanese) brands it's common practice to have Munsell values on their color charts.

How many art products have color data on our website? — 10068

Toplist by medium

Click on a medium to see all Search results with color data (and filter for brand, color, properties)

Yes, for personal use (see the licence). You can download data (including pigment and color notation information) in xlsx or json format from the individual brand pages. You can also download your collections.