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Additive and subtractive color models describe how color is created. They are not competing theories — rather, these models are the two most common and practical ways to create the perception of color. The basis behind these color models lies in breaking the visible light spectrum into its most dominant regions — red, green and blue. In doing so, additive and subtractive color mixing allows the human eye to create a whole spectrum of colors.

The difference between additive vs. subtractive color is in the ways color is created. Let’s discover how these color models differ, which color models are used for what purposes and how to measure additive and subtractive color.

What Is Additive Color (RGB)?

Also known as the RGB color model, additive color is the process of adding one set of wavelengths to another to create a new color — thus the term additive. The visible light spectrum’s primary colors — red, green and blue — are mixed in different combinations and at varying levels of intensity to produce secondary colors.

By adding all the different wavelengths of natural light, the eye sees white light rather than each color. When no light is present, the eye perceives black.

What Is the RGB Color Model Used For?

Today, the additive color model is primarily used to visualize, represent and display images in electronic systems, such as TVs, computer monitors and mobile phones. Because these are light-emissive devices, they start as black and add red, green and blue light to produce the spectrum of colors. When you create a design on your computer or tablet, you use the RGB color model.

Color theory is an integral part of all design processes. In short, color theory assigns a logical structure to color based on light spectrums, highlighting which colors aesthetically complement each other. When you employ the fundamentals of color theory in your design, you can create unforgettable branded products.

The Color Wheel and Color Categorization

Isaac Newton first designed the color wheel in 1666 to orient and observe the harmony of the three primary colors — yellow, blue and red. All colors are derived from a mixture of these three primary hues, which you can then use to create secondary and tertiary colors. However, certain industries may use red, green and blue or cyan, magenta and yellow as their primary colors, depending on the demands of their medium.

The primary colors — yellow, blue and red — combine to create the secondary colors green, purple and orange. No matter the orientation of the wheel, the primary colors are always across from each other and create a triangle. Colors are then categorized by complementary colors, which are located opposite each other on the color wheel. Complementary colors are great for creating eye-catching accents. However, overusing complementary colors might appear garish and overwhelming to your viewer.

You can also mix secondary colors to create tertiary colors like blue-green, blue-purple, red-purple, red-orange, yellow-green and yellow-orange. All tertiary colors are formed by mixing a half-saturated primary color with a fully saturated primary color. Learn more about other types of color mixing below.

Color and appearance measurements for the beverage industry are used to ensure that the overall product appearance is the same from lot to lot. In the marketplace, it is rare that consumers are permitted to taste food products prior to purchasing them. However, they frequently can look at the product. They make a judgment decision largely based on overall appearance including color.

Coloring the mind of your Consumer:

Never has the consumer been more empowered than now in this digital age where knowledge of the products they purchase has been made available to them at a click or swipe, and this testifies that a greater need has evolved for the F&B industry to build a product with enticing visual properties such as Color and haze without compromising the highest level of quality. A strikingly similar parallel of ‘Go-Green’ campaign has also weaved it’s way in the Food & Beverage industry influencing the consumers to choose naturally colored products over artificially bright and unnatural Colored products, and this has birthed the need to test the quality of the beverage for Color consistency across all stages of the process like production and storage as the ingredient changes can alter the base color of a beverage, resulting in the perception that the product is different or of lower quality.

Diverse Optical Characteristics and their Methods for measurements:

The complexity of successfully measuring Color and appearance in the Beverage Industry is further enhanced by the fact that beverages are of types opaque, translucent or transparent, and each form requires different instrumentation and techniques. Opaque liquids have high solids content with a characteristic of high Brix value when light passes through it and Translucent liquids possess medium levels of solids and exhibits a lower brix value when light passes through it. Therefore, it is crucial for the food processors to assess the right measurement modes like reflective or transmittance before they measure the Color during any stage of processing. This significantly increases the need of a spectrophotometer to measure the spectral data values and also measure the transmission haze.

Between the history of color and associations with certain shades in different cultures, color meanings and usage are fascinating to learn about. Here are 10 fun facts about colors.

1. Blue Was Once Seen as a Low-Class Color

In Ancient Rome, royalty wore white, red and black. Those in lower society wore blue. Because the color blue was associated with the working class and barbarians, it was not mainstream. Blue became more acceptable when it became the color of the Virgin Mary’s cloak in the 12th century.

2. Queen Victoria Started the White Wedding Gown Tradition

In 1840, red was the popular color of bridal gowns. Queen Victoria didn’t follow this tradition, wearing a white gown to her wedding instead. Within a few years, white wedding dresses were regarded as the best color for brides.

3. Some Languages Describe Colors and Shades Differently

Tribal African tongues and other languages describe blue and green as different shades of the same color. The Russian language specifies light and dark blue as different colors, not different shades of the same color. Many ancient languages didn’t have a word for blue.

4. Purple Was the Color of Royalty Because It Was Expensive to Obtain

Until 1856, the color purple came from snail mucus. The snails used were almost extinct, and 20,000 were required to get one ounce of purple dye. Since purple was a rare and expensive color, it was only worn by royalty. For commoners, wearing purple was a crime punishable by death.

5. Red Is the First Color a Baby Sees

Infants start to recognize the color red at two weeks old because red has the longest wavelength, which is easy to process. Babies can see the full spectrum of colors at five months.

Color tolerances set acceptable limits for the appearance of a product and are an essential part of quality assurance and quality control processes for color. You can efficiently determine whether a product falls within the limits by establishing tolerances. If it does, the product passes. Failed goods fall outside the tolerances, meaning process adjustments may be necessary to create the desired appearance. 

Many industries, such as food, plastics, and chemicals, rely on accurate appearance. Tolerances enable you to establish a standard and decide how much variation to allow, giving you consistent color outcomes. 

What Is Color Tolerance?

Color tolerances are the parameters within which a product's color can vary yet remain acceptable. Typically, visual assessment is the initial step to define the acceptable color range. Spectrophotometry then objectively and scientifically quantifies and manages those tolerances.

Before establishing tolerance values, you must decide on the observer, choose a color scale, such as Hunter L,a,b, and then select illuminants for comparison, like D 65 and Illuminant A. Depending on what you're measuring, the scale you choose might come from the International Commission on Illumination (CIE), which sets global measurement standards, or from another entity. 

Once you have a comparison standard, you can gather products and measure their color to determine acceptable variations called tolerance values. 

In this process, you start by selecting a relevant standard for your product, then determine how much this standard can vary before it creates visible differences in appearance. This test helps you set boundaries for future production to objectively decide whether products fall close enough to the original standard to conform to quality expectations.

Detecting Color Differences

You can establish tolerances based on two levels of difference:

• Minimum perceptible difference: A visual comparison shows a just-noticeable difference between the standard and the sample. 
• Maximum acceptable difference: The level represents the largest acceptable difference between a standard and a sample. 

Focusing on the maximum acceptable difference means a broader range of acceptable values, while relying solely on minimum perceptible difference can lead to high rejection and material waste. As a result, choosing the right approach is typically industry-driven. For example, the food industry frequently uses the maximum acceptable difference, but pharmaceutical manufacturers usually opt for the minimum perceptible difference.

Range of Tolerance Definition

The range of tolerance is the acceptable level of variation related to an established color standard. You will establish this standard using a measurement model like CIE L*a*b*, which results in three values measuring:

• L*: Lightness, from dark at zero to light at 100.
• a*: Position on the red–green axis, with the positive number indicating red and the negative indicating green.
• b*: Position on the yellow–blue axis, with yellow represented as the positive and blue as the negative.

Once you establish a standard, you can decide on each dimension's tolerance. Here are the formulas for determining the difference (∆) between a sample and a reference:

∆L* = L*sample - L*reference

∆a* = a*sample - a*reference

∆b* = b*sample - b*reference

You can also calculate the total color difference across the three values in a single formula, with the results represented by delta E* (∆E*). Here's the formula to determine ∆E*:

∆E* = √((∆L*)2+(∆a*)2+(∆b*)2)

While ∆E* values can be helpful, use this method carefully. When the difference is spread over three dimensions, you may get a value that looks acceptable but has significant variation in one measurement, such as red vs. green. 

This variation will create a noticeable visual difference but may not impact the delta E* value if the other dimensions are close to the standard. If you calculate the difference values separately, you can more closely monitor each one to verify that none stray too far from the standard.

Vegetable oils such as olive oil and peanut oil must meet consumers' visual expectations with consistent coloring. Vegetable oil manufacturers can please customers and increase profits with color measurement solutions like spectrophotometers.

Among the many challenges facing modern global manufacturers, regulatory compliance ranks at the top. The laws encompass product color standards to uphold consumer safety, advance best practices, and promote standardization. Operations that cross borders also span all these different legal frameworks that cover color and color measurement, from the FDA and USDA to ASTM, ISO, and JIS. Failing to adhere to all applicable standards has real, costly consequences, including material waste, penalties, and fines.

Spectrophotometry is the best solution for ensuring consistent, compliant color measurements. As the universal color translator, these devices provide objective, repeatable data that simultaneously satisfies multiple regulatory frameworks.

Variations in Regional Color Standards and Their Scope

The standards maze goes beyond bureaucratic differences to reflect real industrial priorities and their regulatory enforcement.

Organizations like ASTM and ISO primarily establish measurement methods that instruct manufacturers how to capture readings. For example, ASTM E1164 dictates the geometric conditions required for obtaining spectrophotometric data, such as d/8° or 45°/0°, while ISO 11664 — which is equivalent to CIE standards — defines the fundamental calculations for colorimetry.

In contrast, regulatory bodies like the FDA and USDA rely on these established methods to set the acceptance criteria. For instance, the USDA has specific Color Grades for products like tomato paste and orange juice. Calculating these specific grades requires extracting data using instruments equipped with the correct measurement geometries.

In Japan, Japanese Industrial Standards (JIS) for color measurement align closely with international CIE and ISO principles to ensure global consistency.

As a result, the true challenge for manufacturers isn't documentation and paperwork. It's having the right color measurement solution to bridge these different regulatory frameworks.

The High Costs of Inconsistent Measurement Protocols

Noncompliance with color standards isn't an option. Aside from potential regulatory fines and penalties, violations can lead to:

• Rejection of batches at incoming QC: Customers may turn away entire shipments, essentially doubling shipping costs with return logistics.
• Reworks due to failed color audits: Reformulating, reprocessing, and relabeling products reduces efficiency and profitability.
• Loss of contracts: Manufacturers may face reputational damage and lose future revenue opportunities for failing to deliver to specs and on time.
• Product recalls: If faulty goods hit the market, manufacturers must absorb the costs of recalling the products, which can range into the millions.
• Market exclusion: Repeated violations can result in being banned from selling in certain areas.

Plus, there is a substantial hidden cost to inconsistent measurement protocols — managing separate inventories for different regions. These separate streams mean more variability in raw material colors and less flexibility to redirect products based on demand shifts.

The Pitfalls of Visual Evaluations Across Multisite Operations

Manually evaluating color is an insufficient approach, and one that won't satisfy regulators. The process is unreliable since human color perception varies by individual and observation conditions. Differences in lighting, sample presentation, and operator fatigue will naturally arise, and all can significantly influence the accuracy of your color evaluations.

Visual assessments are also impossible to quantify precisely, so there's no way to document compliance objectively and share that evidence with regulators in other jurisdictions — you can't email a visual impression as proof.