Painters have traditionally used the RGB (red, green, blue) color model rather than the CMYK (cyan, magenta, yellow, black) model preferred for print. There are several key reasons why RGB is better suited to painting than CMYK.
The Nature of Paint Pigments
Paint pigments are reflective materials that absorb some wavelengths of light and reflect others. When white light hits a painted surface, some wavelengths are absorbed and others are reflected back to our eyes, creating the perception of color. Pigments come in various pure hues like cadmium red and cobalt blue. Painters mix these to create the full spectrum of colors.
This is additive color mixing, where combining pure red, green and blue pigments together produces black. This mirrors how RGB colors work on a computer screen. The RGB model matches the innate nature of paint pigments.
Limited CMYK Gamut
While RGB can produce around 16 million possible colors, the CMYK gamut is more limited. Converting RGB values to CMYK always results in a reduced palette. CMYK prints have a hard time accurately representing very saturated hues like neon oranges or purples. The RGB gamut aligns better with the wide range of pigment colors available to painters.
Lighting Conditions
Paintings are viewed under various lighting conditions, from daylight to incandescent bulbs. This changes the way the colors are perceived by the eye. However, CMYK relies on a fixed lighting environment. The cyan pigment assumes a standard daylight temperature, as do the other process colors. This can make CMYK appear dull or inaccurate in other lighting situations. RGB does not have this limitation.
Layering and Transparency
Painters build up colors through layering transparent glazes and opaque passages. This allows more light to reflect back from lower layers. RGB can represent these transparent effects since it is an additive color system. The opacity of paint layers has no analogy in the CMYK process. RGB aligns better with painters’ layering techniques.
Mixing Neutrals
With RGB, combining all three primaries produces a neutral black or gray. This again mirrors mixing paint pigments. However, in CMYK, combining cyan, magenta and yellow does not create a perfect neutral. Instead it produces a muddy brown hue. To achieve true neutrals, black ink must be added. This does not correlate to mixing paints.
Color Gamut Comparison
| Color Model | Approx. Number of Colors |
|---|---|
| RGB | 16.7 million |
| CMYK | 700,000 |
As this table shows, the RGB gamut encompasses over 16 million possible colors, while CMYK is limited to around 700,000 reproducible colors. RGB can represent many more highly saturated pigments.
Lack of Fixed Standard
While CMYK relies on a fixed set of standards and ink densities, painters can individually modify paint pigments and mixtures. Two artists using the same tube of ultramarine blue may end up with differing hues depending on dilution, layering and other adjustments. RGB allows for this type of customization and alteration of individual colors.
Preparing Digital Reproductions
Painters must consider preparing accurate digital images for portfolios, online galleries and reproductions. Shooting paintings in RGB provides files better suited for online presentation and digital printing. Starting with CMYK may restrict options later on. Capturing artwork using RGB gives maximum flexibility.
Lack of Cyan and Magenta Pigments
While paint lines include pure red, blue and yellow pigments, there are very few cyan or magenta paints. These must be mixed by the artist. Most painters think innately in terms of the primary colors rather than cyan and magenta. The RGB model aligns with the tradition of red, blue and yellow pigments.
Prevalence of RGB Digital Displays
We live in a world surrounded by RGB screens. Modern media is colored in RGB. Painters reference photos, videos and artwork seen on phones, tablets, monitors and televisions when creating. They must consider how their paintings will translate to these RGB displays. Using RGB from start to finish maintains fidelity and accuracy.
Ease of Digital Color Picking
Digital color picking tools report values in RGB. This includes apps for selecting colors from reality. For example, holding your phone camera over a flower converts its colors to RGB values. Painters use these digital tools to sample and match colors when working. Starting in RGB makes this process seamless.
Looking Forward to New Technologies
As art moves into new technologies like digital painting apps, virtual and augmented reality, and generative art, RGB will continue to be the norm. Forward-thinking painters build their skills around the RGB model to be prepared for the future of art.
Conclusion
Painters gravitate towards RGB over CMYK because it better represents the innate nature of paints and human color perception. The capacities for more vibrant hues, mixing neutrals, representing transparency, and adapting to different lighting give RGB a clear advantage. Digital display and reproduction considerations also make RGB the logical choice for painters in the modern era. While both color models have their uses, painters find greater alignment with the RGB approach. Their time-honored craft is finding new expression through this versatile digital color model.