Analyzing the Color of Scarce and Expensive Pharmaceutical Materials via Small Sample Testing
small sample testing
Many pharmaceutical companies choose to test small sample sizes when the cost of the product is especially high. Image Source: Shutterstock user Iryna Imago

In an ideal world, drug manufacturers could test large batches of any material for color consistency and quality. However, this isn’t a reality for many pharmaceutical companies. Often, the active ingredients that go into a life-saving cancer treatment or a promising new Alzheimer’s medication are expensive to develop, difficult to synthesize, or made from rare, finite natural resources. This means that drug manufacturers have to carefully measure out their test samples, and in some cases, the material is so expensive that they need to be particularly frugal with their sample sizes. For instance, Soliris, a drug used to treat a very rare genetic condition called atypical hemolytic-uremic syndrome, is one of the most expensive medications in the United States—it sells for $18,000 per dose.1 In order to perform quality control tests on an expensive medication like this, manufacturers typically opt for the smallest sample sizes possible to avoid wasting product.

But when your sample size decreases, it can make the color measurement process much more complicated, as many color measurement instruments are incapable of accurately analyzing the color of very small samples; the equipment is typically designed with larger sample sizes in mind, and these one-size-fits-all tools lack the accessories required to measure micro samples. However, there are a number of high-quality spectrophotometric instruments and accessories on the market that are designed specifically to measure small samples with the highest degree of accuracy. When you use one of these instruments in your lab, you can significantly shrink your sample size requirements, helping you preserve valuable materials.

Why Color Consistency Matters

Measuring the color of your pharmaceutical products is important for two primary reasons. First, the color of a drug can help you determine whether there are impurities or contaminants in your sample; if a liquid cough suppressant is supposed to be completely clear, yet your spectrophotometer detects a yellow tint, then it’s possible that your sample was contaminated, or that there is something wrong within your manufacturing line. The second reason color measurement is important is customer perception. Generally, customers are more likely to trust medications that are consistent in color from pill to pill or batch to batch. Additionally, studies have shown that the color of a medication can impact users’ perception of sensory experience and efficacy. The color of medication can even affect whether users adhere to their prescribed medication plans, making color critical to ensuring therapeutic benefit.2 However, when you’re working with scarce or costly medications, the color quality control process can also grow expensive or even compromise medication supply. You have to waste a certain amount of product in order to test for color consistency, and the more expensive your product is, the greater impact your test sample size has on your bottom line and the availability of usable medication.

small sample testing
Testing small liquid samples requires the use of specialized color measurement accessories. Image Source: Shutterstock user Davizro Photography

High Manufacturing Costs Require Smaller Test Samples

There are a number of reasons medications are expensive to produce. Some of the most notoriously expensive pharmaceutical products, for example, are biologics. This category of medicine includes vaccines, antibodies, and recombinant proteins (made when a lab joins genetic material from different sources). It’s the fastest-growing category of products in the pharmaceutical industry; in 2008, biologics made up almost 30 percent of the 100 top-selling drugs in the world and that number is increasing. Biologics are manufactured using a biological process, not a chemical process. Because these products are made from raw materials that are rare and difficult to produce, the price of these products is typically much higher than it is for drugs made using synthetic chemical processes; just one dose can cost as much as $10,000.3

If you manufacture your products using any rare raw materials, the scarcity and extra cost associated with these ingredients may force you to use smaller sample sizes when testing for color consistency. For instance, some chemotherapy drugs contain platinum, which is among the most expensive metals in the world.4 Another chemotherapy drug called Taxol is made from the bark of an extremely rare tree, the Pacific yew. These trees only exist in old-growth forests in the Northwestern United States, and it takes at least 60 pounds of bark to produce enough of the drug to treat just one patient.5 Because this resource is finite, manufacturers must handle their test samples with care. Regardless of the reason for high cost or scarcity of material, many pharmaceutical manufacturers can benefit from small sample testing; the less product you waste during testing, the more product you can put into the hands of those who need these invaluable medications.

small sample testing
Small sample accessories can help you test expensive materials without wasting more product than necessary. Image Source: Shutterstock user Syda Productions

How to Measure Small Sample Sizes

To test an especially small sample size, you’ll need a repeatable measurement method designed accurately analyze your sample size. Many of HunterLab’s spectrophotometers are compatible with specialized accessories that allow you to accurately test small and micro sample sizes consistently. The accessory that you will find most beneficial depends on the type of product you’re manufacturing, what the minimum size of your sample will be and the type of spectrophotometer that you already have in your lab. These may include:

Measuring Powder Samples in Reflectance Mode

If you’re working with powders, you’ll need to modify your spectrophotometer’s port plate in order to get accurate color measurements from a very small sample size. HunterLab instruments that include a Small Area View (SAV) option can be equipped with a smaller port plate as an accessory. In addition to the smaller port plate, you can use a special powder holder that measures about 0.4 ccs of pressed powder. To use this method, simply place your powder sample into the holder, pack it down with the plunger that comes with the accessory, and then place it inside of the port plate, where it will be measured via the clear window on the holder. 

Measuring Solid Samples in Reflectance Mode

If you’re working with any small solid samples, then you’ll need to reduce the size of the port opening on the spectrophotometer. This will allow you to view the sample without a background. Many of HunterLab’s spectrophotometers are able to switch from a Large Area View to a Small Area View automatically, using a motorized component. To use a SAV on your small solid sample, you should operate the instrument via the retroviewer option so that you can ensure that the entire solid sample covers the port opening. Be aware, however, that your sample size needs to be at least as large as the openings (4 mm or 3 mm, depending on the instrument).

Measuring Liquid Samples in Transmittance Mode

If you’re working with liquids, you’ll need a specialized semi-micro cell holder for your samples. HunterLab has a semi-micro cell holder accessory available that includes beam-reducing optics to take accurate measurements of small liquid samples. This accessory needs to be installed in the transmission compartment of the instrument. A typical 10mm pathlength cell requires 3500µL of solution, HunterLab offers mirco and ultramicro cells that can be measured with a little as 300µL of solution.   

HunterLab Innovation

With specialized accessories like smaller port plates, semi-micro cell holders, and powder holders, HunterLab provides reliable solutions for even the most exacting color measurement challenges. Our instruments are designed to meet the high standards set by the pharmaceutical industry, and over the past 60 years, we have been a leader in dependable color measurement of liquid, solid, and powdered medications. Contact us today to learn more about our spectrophotometers, customizable software packages, and world-class customer support services and let us help you select the right tools for your needs.

  1. “Why is Soliris the Most Expensive Drug in the US?”, May 27, 2017,
  2. “How Pill Color Affects Drug Adherence”, May 9, 2016,
  3. “Why is Biomanufacturing So Hard?”, July 15, 2011,
  4. “Why is Platinum in Some Chemotherapy Drugs, and Can We Improve Them?”, April 14, 2017,
  5. “Drug Made from Rare Tree is Approved to Treat Cancer”, December 30, 1992,
The Benefits of Simulating Daylight Using UV Control
simulating daylight
UV control allows you to test the color of your products as they are seen under daylight conditions. Image Source: Unsplash user Breather

Have you ever noticed that printer paper appears even more brilliantly white when you view it outside in the direct sunlight than it does inside under the the warm glow of an incandescent lighbulb? This is no coincidence. Paper manufacturers frequently use Fluorescent Whitening Agents (FWAs) that are designed to absorb UV light, and then re-emit it back at the viewer in the blue end of the visible spectrum.1 This re-emitted light produces a brightening effect on the paper, making it appear even whiter to the naked eye. In addition, FWAs may also compensate for yellow paper coloration or other variations in color. In other words, manufacturers can use UV light, natural light and different-colored light sources to make their products appear even brighter, and thus, more visually-appealing to customers.

However, while FWAs are an essential material in some industries, such as paper, textile, and plastics, they also make accurate color measurement more challenging. FWA-enhanced samples can appear dramatically different in color to the human eye depending on whether the product is viewed outdoors, or under artificial lighting conditions. The color of the light source also has an impact on the appearance of the product. This is one of the reasons UV control is essential for color measurement—it allows you to account for many different lighting conditions, including daylight and indoor environments. Using spectrophotometers with UV control options, you can get a more accurate color reading on your FWA-enhanced products, allowing you to view your products exactly as your customers will see them.

What is UV Control?

The ultimate goal of UV control is to obtain more accurate color readings of your samples under various lighting conditions. In natural daylight conditions, UV control essentially allows you to view the sample as the human eye would see it outdoors. To accomplish this, many spectrophotometers attempt to match the CIE standard illuminant D65. Commonly called the “daylight illuminant,” D65 closely matches the amount of light that you would see on a clear afternoon in Northern or Western Europe.2 Spectrophotometers have the ability to simulate these conditions in the lab, producing a consistent environment in which to test samples.

This is where UV control comes into play. UV control options include the use of xenon light sources, motorized UV filters and calibrated fluorescent standards. Each of these options can dramatically improve the accuracy of your color measurements when testing FWA-enhanced samples. In spectrophotometers, UV control works by allowing you to see products as they appear under natural, UV daylight conditions. This is helpful for industries that use FWAs, as you can measure exactly how the product appears to your customers, even if you measure the product in an indoor, controlled lab setting—it simulates daylight conditions for you.

simulating daylight
Paper manufacturers often use FWAs to enhance the appearance of their products under UV light sources. Image source: Pexels user Tirachard Kumtanom

Achieving Accurate Color Measurements for Whitened Products

One of the most important benefits of UV control is the ability to obtain accurate color measurements for bleached or fluorescent white products. The problem with products that have been dyed with FWAs is that traditional whiteness measurement standards may not be accurate. The FWAs interact with the UV light, which can cause a variation between the whiteness index measurement and how the human eye perceives the color of the product. In other words, the spectrophotometer may not measure the color accurately, according to how your customers will see it. UV control corrects for this by calibrating the spectrophotometer so that it corresponds to a specific UV standard. So, if you wanted to test your product’s appearance under simulated daylight conditions, then you could calibrate your spectrophotometer so that it controls the amount of UV light emitted, allowing you to see your products as your customers will see them under those conditions.

UV Control Methods for Fluorescent Samples

The UV control method that you use to measure whitened products will depend on what type of measurement you want to make. If you want to measure your product as it would appear in outdoor lighting conditions, then you may use UV calibration and fluorescent standards to achieve this. Many of HunterLab’s spectrophotometers offer UV control and are supplied with fluorescent standard calibrated to a Ganz whiteness value traceable to the Hohenstein Institute in Germany. From here, the software in the spectrophotometer automatically reads the fluorescent standard and adjusts the motorized UV filters until the calibrated Ganz value is achieved. You can repeat this process monthly, or whenever you change the instrument’s lamp.

Alternatively, you can eliminate UV entirely, allowing you to view the sample as if it were indoors under incandescent or LED lighting which has limited or no UV content.  To do this, you can insert the spectrophotometer’s UV filters completely and take a measurement of the sample without UV interference. You can then compare this measurement to one made while the UV filter is in its normal position—this should tell you exactly how much impact the FWAs have on the final color of your product. By using one or more of these methods, you can accurately test your fluorescent samples under a variety of lighting conditions, including simulated daylight.

simulating daylight
Many spectrophotometers are equipped with xenon light bulbs, which closely mimic natural daylight conditions. Image Source: Pexels user Pixabay

UV Control Compensates for Lamp Age

In addition to helping you accurately measure fluorescent white samples, UV control can also extend the use of your lamps over time. As your light source ages, its illuminating qualities may change. The bulb often begins to dim, and this in turn can impact the results of your color measurement tests. When you perform UV calibration every week, or whenever you change your light source, your spectrophotometer will adjust to the new conditions, compensating for the difference in light source. If you have a lamp that is capable of flashing one million times throughout its lifetime, this is an essential tool. UV control will ensure that every flash that lamp makes, whether it’s the first time or the 30,000th time, will lead to accurate measurement results.

Achieving Illumination Agreement Between Different Instruments

One final benefit of UV control in spectrophotometers is that you can ensure more accurate readings between multiple instruments. Illumination agreement between different color measurement instruments can be a challenge—an instrument with an older lamp, or one that uses a tungsten bulb may get a very different color reading compared to an instrument with a newer lamp, or one that uses xenon bulbs. In addition, xenon bulbs are a closer match to the D65 standard compared to halogen bulbs, and this will have an impact on how these different instruments measure color. UV control takes some of this variation out of the equation, since you can calibrate for this change of light source in advance. The result is a more accurate color measurement protocol that works well for a wide range of industries, and that is designed to last for the entirety of the instrument’s lifetime.

HunterLab Options

HunterLab carries a wide variety of spectrophotometers that contain built-in UV control options. The LabScan XEs, UltraScan Pros and the UltraScan VISes are all capable of accounting for UV light variations. Moreover, many of these instruments take UV control one step further—you can adjust the spectral distribution of the xenon lamp to more closely match the D65 illuminant, meaning that you can achieve even more accurate color measurements. Contact us today to find out more about our spectrophotometers and how UV control can enhance your quality control processes.

  1. “Fluorescent Whitening Agents”,
  2. “Illuminant D65”,
Spectrophotometric Color Measurement Helps Optimize Appeal of Over-the-Counter Medication
over-the-counter medication
The color of OTC medication influences how consumers perceive its quality. Image Source: Shutterstock user Corinna Haselmayer

A man suffering from a bout of heartburn walks into his neighborhood grocery store hoping to find an antacid that will relieve his symptoms. He heads straight for the over-the-counter medication aisle, but he sees that there are almost two dozen different brands of antacid sitting on the shelves. He isn’t sure which one to choose. Should he go with the antacid tablet that is a calming shade of pale pink? Or is the bright green tablet a better choice?

According to research, many customers in this position would pick the pale pink option. In a study published in the International Journal of Biotechnology in 2010, researchers at the SIES College of Management Studies found that people were more likely to perceive a pink medication as sweet and pleasant, whereas they perceived green medication as sour or bitter.1  This may be because many people associated the color green with acidity, which would be unappealing for those suffering from acid reflux.

This study is part of a growing body of evidence showing that color can dramatically impact perception of medication efficacy and overall user experience. As a result, color becomes a significant factor in consumer behavior and, consequently, the commercial success of medications. This phenomenon is particularly relevant for over-the-counter medication manufacturers. Unlike prescription drugs, which are recommended to patients by doctors, over-the-counter (OTC) medications rely heavily on consumer perception for sales. As a result, OTC medication manufacturers must rely on spectrophotometers to ensure that their products are as aesthetically pleasing as they are effective.

over-the-counter medication
With so many OTC medication brands on the market, it’s important for manufacturers to create colorful products that stand out. Image Source: Shutterstock user mayakova

The Impact of Color on Customer Perception, Adherence, and Habits

Households in the United States spend an average of $338 per year on OTC medications, and 81% of adults say that they use OTC drugs as a first response to most medical problems.2 However, the OTC drug market is competitive and pharmaceutical manufacturers must take color into consideration when developing their products in order to ensure optimal appeal, as color consistency has a significant impact on consumer behavior. For example, one study published in JAMA Internal Medicine in 2013 found that patients who have epilepsy were less likely to adhere to their to their medication schedules if the color of their medication changed during the course of treatment.3  In fact, patients were 53% less likely to take their medication on time if they were given a different-colored pill than they were used to, potentially compromising treatment outcomes. As such, it’s critical to ensure color consistency in all medication products to facilitate adherence.

Additionally, consumers associate different colors with treatment of different conditions. In a groundbreaking study, psychologist Dr. Max Lüscher examined the connection between drug color and the treatments people associated with them.4 While conducting his famous color psychology test, Lüscher found that people most commonly associate orange or yellow with stimulant drugs, olive green or light brown with laxatives, and cough suppressants with light blue or maroon. As a result, some OTC drug manufacturers choose to create products that align with these color associations; colors act as a kind of visual shorthand for the consumer.

In some cases, drug manufacturers can even reinvent consumer color associations. When Pepto-Bismol first hit the market nearly 100 years ago, it was an unusual shade of pink that consumers hadn’t seen before. The source of the hue was the product’s active ingredient, bismuth subsalicylate, which is naturally pink in color.5 While the pink color became strongly associated with the brand itself, it also came to signify antacid medication as a whole. Today, many antacid manufacturers will go out of their way to dye their products pink, even if they use active ingredients that are a different color. This is because studies have found that using a color other than pink can confuse customers, who have come to so strongly associate pink with antacid medication that they may believe non-pink medication is used to treat a different ailment.

over-the-counter medication
Pink medications are often perceived as tasting sweeter compared to green, red, orange or yellow medications. Image Source: Shutterstock user Yuriy Golub

Spectrophotometers Can Help You Achieve Color Consistency

Spectrophotometers play a critical role in creating the ideal pharmaceutical hues and maintaining them from batch to batch, assisting OTC drug manufacturers throughout product development and manufacturing processes. First, pharmaceutical manufacturers can use spectrophotometry during the formulation stage in order to develop the perfect color for every product in their line. Using spectrophotometric data, you can set unique color tolerance standards for each product. From here, your future products can be compared to this guideline to ensure color consistency. Whether you formulate a dusty pink-colored antacid or a bright yellow allergy medication, the spectrophotometer’s software can tell you with great accuracy whether your product falls within the color tolerance that you’ve set. As such, operators can be quickly alerted to unwanted color variation, allowing for corrective action. In pharmaceuticals, this is essential not only for aesthetic reasons but because incorrect coloration could indicate incorrect formulation or processing, both of which may have serious health implications.

OTC medications, of course, come in many different formats, from pressed pills to capsules to liquids, which each has their own unique properties that influence color measurement. As such, the spectrophotometer you choose must be appropriate for the material with which you are working:

  • Liquid Medications: The color of liquid medications can be measured using reflectance or transmission instrumentation depending on whether the product is opaque, transparent or translucent. HunterLab’s UltraScan Pro, UltraScan VIS and Vista instruments are all capable of measuring liquid products and each have unique benefits.
  • Pills and Capsules: When measure pills and capsules , you’ll first need to consider whether your products are opaque, translucent or transparent, just as you would with a liquid product and choose either a reflectance or transmission instrument suited to your needs.
  • Powdered Medications: For color measurement of powdered medications, or for powders that will eventually be pressed into pill or cream form, a Directional 45°/0° reflectance geometry is preferable as it measures color the way the eye sees it. Hunterlab offers a range of instruments designed to handle loose powders and pressed powder plaques, including the LabScan XE, includes an automated zoom lens that allows you to measure very small samples.

With the right instrument, you can achieve greater insight into pharmaceutical color than ever before and implement the most rigorous color quality control processes possible to promote product appeal, ensure product safety, and facilitate customer adherence.

HunterLab Reliability

For more than 60 years, HunterLab has worked closely with the pharmaceutical industry, helping manufacturers establish and adhere to color standards. Using advanced spectrophotometers and color measurement software, OTC drug manufacturers can now ensure that every product is correct and consistent in appearance, whether you are working with liquid medications, pills, capsules, or powders. Contact us today to find out more about our state-of-the-art spectrophotometers and let us help you find the perfect tool for your unique needs.

  1. “Color Psychology in Medicine”,
  2. “Statistics on OTC Use”,
  3. “Variations in Pill Appearance in Antiepileptic Drugs and the Risk of Nonadherence”, February 11, 2013,
  4. Pharmaceutical Dosage Form, April 19, 2016,
  5. “Packaging Defines the OTC Market”, 2005,
Spectrophotometers are Essential for Creating Colorful Luggage
luggage color
Brightly-colored pieces of luggage are often easier to identify in busy airports, making these desirable products for frequent travelers. Image Source: Shutterstock user Nick Starichenko

A traveler has finally reached his destination after a long international flight. He’s eager to get to his hotel and relax, but first, he has to wait for his luggage to arrive at baggage claim. The traveler watches hundreds of plain black suitcases circle the baggage claim turnstyle—each one looks almost identical, and his fellow travelers have a difficult time identifying their own luggage in the sea of black and grey. That’s when the traveler spots his suitcase; it’s a vibrant shade of hot pink that’s nearly impossible to miss. He’s able to quickly claim it and continue with his day.

An estimated 21.6 million bags were lost at airports worldwide in 2016—that’s nearly six bags per every 1,000 airline passengers. And in about 4 percent of these cases, passengers never picked up their luggage from baggage claim.1 In many cases, this is due to misidentification; either a passenger picks up someone else’s luggage by mistake, or a passenger isn’t able to locate the luggage on the carousel.

In both cases, having a distinctively colored suitcase may have prevented the mix-ups from happening. This is part of the reason luggage manufacturers are increasingly choosing to create bags that feature unusual colors, making it easier for their customers to identify their suitcases in a crowd. But having more colorful design options also necessitates better color quality control protocols. Color measurement instruments like spectrophotometers can help you create colorful luggage that stands out from other bags on the market.

luggage color
Reframing of luggage as fashion accessories have led to a proliferation of vibrant colors. Image Source: Shutterstock user Thitirat J13

How Unique Colors Benefit Customers and Luggage Manufacturers

While many customers still prefer to use black or grey luggage, colorful designs are becoming more popular due to both their aesthetic appeal and practical function. In the past, suitcases were primarily viewed as utilitarian objects and were typically offered in a limited range of colors. Today, however, luggage is increasingly regarded as an exciting fashion accessory, which is why many brands are using brighter or more unique colors.

Modern luggage manufacturers often create suitcase shells from scratch, and there’s an almost unlimited number of color options available to them. Travel blogger Samantha Brown says that we’re in “the dawning of the age of colorful and stylish luggage.” She explains, “Hard case luggage has taken this to a new level, with incredible designs that become movable art.”2 By choosing a color other than black, grey or navy, customers can not only identify their luggage more easily but also ensure that their suitcase matches their personalities and preferences.

For luggage manufacturers, offering unique colors can both help establish brand identity and increase the appeal of their product lines. High-end manufacturers like Louis Vuitton create their own textiles that prominently feature the hallmarks of the brand, such as their signature monogram logo and brown color scheme.3 However, many manufacturers build their brand and attract business not with a single signature color, but through the variety of their offerings, giving customers appealing choices and keeping up with color trends.

Measuring Color Using Spectrophotometers

Color measurement instruments like spectrophotometers can help you establish your product colors with a great degree of accuracy. Unlike the naked eye, which can be biased when it comes to accurately measuring color, a spectrophotometer allows you to objectively analyze color to ensure consistent evaluation. This means that color assessment will be the same every time, regardless of operator.

The color of your luggage is influenced by a variety of factors, including the type of material you use and how the material is handled during manufacturing. Spectrophotometric color measurement can help you establish an objective color standard and evaluate your processing methods to ensure coloration is accurate and consistent, taking into account the impact of each process variable. For example, if the color of a plastic suitcase does not meet your color requirements, you may have to modify your pigment ratio in order to achieve the look you want. Similarly, a soft-sided bag may require a different dye formulation to adhere to your standard. Once you’ve refined your manufacturing process to achieve the perfect color, you can then continuously monitor color within the production line to identify unwanted color variation.

luggage color
Color can help your luggage stand out on the baggage carousel. Image Source: Shutterstock user NeoStudio1

Testing Various Materials for Color Cohesion

One of the challenges associated with creating color cohesion in luggage is that each piece of luggage can be made from a wide range of materials. Additionally, disparate pieces of luggage may have to match in color despite being made of completely different materials.4 For example, some luggage brands offer both hard-sided and soft-sided cases in a signature color, as this gives their customers more freedom to choose the style that they prefer without having to compromise on aesthetics.

However, each material has its own unique aesthetic qualities, which can present difficulties for color matching. For example, a glossy, smooth plastic sample will appear to be different in color than a matte, textured sample, even if the two are identically pigmented. State-of-the-art spectrophotometers can help you create consistent color matches between disparate materials, which is essential for luggage manufacturers who want to achieve color consistency within individual products and across a product line. Depending on the type of instrument that you use, spectrophotometric color measurement methods can help you test a wide range of materials, from shiny metals to woven fabrics to bold plastic shells. Using these tools, you can create colorful, cohesive products regardless of the materials you choose.

HunterLab Experience

HunterLab provides color measurement instruments to seven of the world’s top 10 fabric manufacturers, and our instruments are well-designed to meet the demands of the woven fabric industry. In addition to our experience in the textile industry, we also provide reliable color measurement instruments to the plastics industry and many of the world’s top plastics manufacturers use our state-of-the-art equipment to create their high-quality products. Contact us today to speak with one of our color quality experts and let us help you select the perfect spectrophotometer for your needs.

  1. “What Happens to Lost Luggage?”, August 22, 2017,
  2. “Six Things to Consider When Buying Luggage”, January 2, 2014,
  3. “Ten Best Luxury Luggage Lines”,
  4. “Luggage Materials”,
Spectrophotometers Ensure Color Accuracy and Consistency in Stucco
stucco color
Brightly-colored stucco walls can help buildings stand out in crowded city centers. Image Source: Flickr user Jose Ramon Polo Lopez

If you’ve ever taken a road trip across the United States, you may have noticed that fast food restaurant buildings all have virtually the same appearance from franchise-to-franchise. When you visit a Taco Bell in Nevada, you’ll see almost the exact same pale orange stucco on the front of the building as you see on Taco Bell buildings in Florida and Wisconsin. This is because most restaurant chains make a conscious effort to carefully match the appearance of the stucco on each building.1  Not only does this color matching process make the buildings look more cohesive, it also helps businesses establish a unique and easily recognizable brand.

However, getting two shades of stucco to match isn’t always easy. Inconsistencies in the formula and pigments used can dramatically alter the overall appearance of stucco products. Additionally, the rough texture of the final application may cause the stucco to appear lighter or darker in color to the naked eye, even if the stucco mix is a perfect color match. To solve these common manufacturing problems, stucco manufacturers can use spectrophotometers to ensure that every product meets ideal color standards. Unlike the naked eye, which can be unreliable when it comes to accurately detecting small variations in color, a spectrophotometer provides manufacturers with the most accurate color readings possible, allowing them to create more reliable, aesthetically-pleasing building finishes.

The Value of Color Accuracy and Consistency

The appeal of stucco lies primarily in its appearance. While it provides minimal protection against the elements, stucco is frequently used to cover up more protective layers of materials, such as concrete or wood, to open up new aesthetic possibilities.2 Because the main purpose of stucco is to make a building appear more beautiful, color quality control is of utmost importance.

Contractors like to use stucco because manufacturers can mix a wide range of color pigments into the material to create virtually any color the customer would like. Whether customers are looking for a deep, rich red material, or a creamy eggshell white, manufacturers can easily mix the perfect percentage of pigment into every product. The only problem is that this color must be perfect from the moment it’s applied to the building—while you can paint over stucco, this process is time-consuming, labor-intensive, and difficult process. As such, stucco manufacturers have to get color right the first time.

However, color doesn’t just have to be consistent within a single building project. Because brands often use the color possibilities of stucco to fortify brand identity, color must also remain consistent over time and across geographic locations. This color consistency is essential to making brands easily identifiable to customers; too much variation in color can compromise customers’ perception and disrupt the sense of familiarity trademark colors seeks to elicit.

stucco color
If you want to change the color of a stucco wall, you have to apply a brand new layer of stucco on top of the existing wall if you want to avoid the time-consuming work of painting. Image Source: Unsplash user Landis Brown

Acrylic vs. Traditional Stucco Colors

The risk of significant color variation in your stucco products depends on whether you’re creating acrylic or traditional stucco.3 Acrylic stucco is made from resins or polymers mixed with liquid pigment and a small percentage of sand (for texture). Because the colors and the stucco mix all have a liquid consistency, the pigments tend to blend seamlessly with the resins and polymers in the product. The result is a very colorful product with minimal risk of batch-to-batch variation.

However, traditional stucco is a bit more complicated to create. This material is made using a mix of Portland cement, white sand, lime and water. Unlike an acrylic product, which resembles wet paint in its raw form, traditional stucco is usually a dry mix, in powdered form. Because the texture is a powder, pigments don’t always mix as seamlessly into the product as they do with a liquid mix. You’re more likely to see color variations between batches and color quality control is much more challenging.

Spectrophotometers Can Help with Both Stucco Styles

Whether you’re creating acrylic or traditional stucco, a spectrophotometer can help you achieve the consistency you desire.4 In an acrylic product, you can monitor batch-to-batch color consistency and perfect new formulations using spectrophotometric data. Spectrophotometers can help you provide a wide range of color options for your customers, and, moreover, you’ll know exactly how much pigment to mix into every batch in order to attain specific colors.

Meanwhile, if you use a spectrophotometer while mixing traditional stucco, you can limit some of the naturally-occurring color variation in these products. While you may not be able to achieve the same exacting color consistency as you would with an acrylic product, you can prevent your products from showing signs of significant color variation by identifying unwanted color disparities early.

stucco color
The texture of stucco can alter the overall color appearance. Image Source: Wikimedia user Dante Alighieri

How to Achieve Stucco Color Consistency

The type of spectrophotometer that you use to test your stucco samples is determined by what you want to achieve and what type of samples you plan on measuring. A portable instrument is primarily used to test samples outside of the lab, and manufacturers can use them directly on the production floor or construction site. Meanwhile, benchtop spectrophotometers remain in one place and are used in a controlled lab setting.

In addition to measuring samples in their raw form, manufacturers may also want to test new products as they appear after application. This is especially important when testing a new formula or color offering. After application, the product dries down and the rough texture of the stucco may make the product appear lighter or darker than it did in the liquid or powdered stage. A spectrophotometer that is capable of measuring color based on how the human eye perceives it will take the total appearance of the stucco into account, allowing you to adjust your formula to get the perfect final application color.  

HunterLab Reliability

HunterLab has over 60 years of experience working closely with architects and construction material manufacturers, helping them find the perfect color measurement tools for their needs. By focusing on color quality control for your products, you ensure that every material you craft is as high in quality as possible to satisfy the needs of your customers. Contact us to find out more about our renowned spectrophotometers and let us help you select the right instruments for your needs.

  1. “The Use of Calibrated Digital Photography to Match and Evaluate Color Differences in Masonry Repairs”, October 9, 2010,
  2. “Pros and Cons of Stucco Homes”,
  3. “Acrylic Stucco vs. Traditional Stucco”,
  4. “The Science of Color”,
How to Accurately Measure Color in Clay and Terracotta Products
clay and terracotta
Terracotta products, like gardening pots, are a popular tool for homeowners and garden designers. Image source: Pexels user

A garden designer has spent months searching for the perfect teal-colored pots and planters for a new urban green space located on the rooftop of a massive apartment complex. The designer wants the rooftop garden to look beautiful and cohesive, and so she carefully selects plants and pottery that will complement each other.1 Similarly, architects use well-crafted terracotta tile as roofing, flooring, and decorative elements, making buildings appear more colorful and aesthetically-pleasing. In both cases, customers rely on colorful, unique clay products to make their visions come to life.

Color is one of the most attractive features of clay and terracotta products; the right shade can completely transform the appearance of a space or building. As such, manufacturers must take color quality control into serious consideration and integrate spectrophotometric technologies in their production process. Spectrophotometric color measurement helps ensure that each product conforms to your aesthetic expectations, helping you make the most of these colorful materials.

clay and terracotta
Terracotta is naturally orange in color due to the oxidation of iron that occurs when the product is exposed to high temperatures. Image source: Shutterstock user Pi-Lens

The Benefits of Spectrophotometry for Clay and Terracotta Products

The color of terracotta and clay products can be influenced by a wide variety of factors. The traditional color of terracotta is orange, yet the material can also take on a red or brown hue if it’s left in the kiln for a long period of time. In order to get this trademark look, you need to use an effective color quality control process to ensure that each product is the perfect shade of burnt orange. However, many modern industries also choose to create terracotta and clay products that deviate from their traditional colors. Today, it’s not unusual to find clay and terracotta products in a range of hues, and designers, architects, gardeners, and homeowners often search for shades that match a specific color scheme. This is why quality control is essential, whether you’re manufacturing a traditional product or experimenting with new, exciting colors.

Spectrophotometers are essential for achieving color quality control.2 In part, this is due to the fact that these instruments are capable of detecting small variations in color that the human eye may not immediately see. Additionally, the naked eye is subjective when it comes to accurately assessing color samples, as environmental factors and biological limitations can result in variations in color perception between viewers or even when the same viewer observes an object at different times. Spectrophotometers eliminate this subjectivity; instead, they capture objective color data to ensure accuracy and consistency in your finished products.

Measuring the Color of the Product’s Raw Materials and Finish

Not only do spectrophotometers help you ensure accurate color quality control of finished product, these instruments can be used to test the impact of raw materials before the general production process begins. In particular, assessment of glaze can be a critical step in your quality control process, as the color and turbidity of your glaze can dramatically impact the final color of your product. Even the smallest variation in color could be grounds for concern, especially in large production runs of terracotta and other clay products.  However, the impact of glazes can only be fully observed once applied and fired. As the authors of Ceramic Material Systems: in Architecture and Interior Design note, “In most processes involving glazes, test tiles or prototypical samples are made to ensure the glaze mix is consistent with expectations.”3 This prevents manufacturers from creating an entire batch of products that have serious color flaws, which in turn results in less product waste. After your samples comes out of the kiln, you can also apply and test additional finishes, such as paint or an additional glossy, protective coat of glaze, which may be similarly assessed.

clay and terracotta
Spectrophotometric color measurement is valuable in assessing the color of glazes on clay products. Image Source: Shutterstock user Thirteen

Testing Proper Kiln Firing Times and Temperatures

In addition to assessing glazes and finishing, spectrophotometric color measurement can be used to establish appropriate kiln firing times. The color of your product may change depending on your kiln’s temperature and the amount of time that your product spent inside of it. This is particularly true of terracotta because its degree of color develops as it’s exposed to high heat; the iron in the clay oxidizes, deepening the color of the product. Generally, the longer your product spends in the kiln and the higher the temperature, the darker your final product will be. However, firing times can impact the color of non-terracotta products as well.

When you create a new product, you may use a spectrophotometer to find the perfect firing time—you can test a sample of clay or terracotta at different temperatures and bake times to find the time and temperature that gives you the ideal shade. Spectrophotometers can then be used to measure future products to ensure adherence to your color standard, alerting you to unwanted color variation that could indicate potential temperature or firing time inconsistencies. This could save you from over-firing or under-firing future batches of product, minimizing waste.

HunterLab Quality Control

For more than 60 years, businesses have relied on HunterLab’s state-of-the-art spectrophotometers to ensure that their products meet color standards. Our instruments are flexible, user-friendly, and come in a variety of different formats designed to meet the needs of a range of industries. With a complete line-up of portable, benchtop, and on-line instruments, HunterLab spectrophotometers offer solutions for color measurement in a wide variety of applications. Contact us to find out more about how our instruments can help you improve your color quality control process.

  1. “Rooftop Gardening”, October 23, 2017,
  2. “Technology and Innovation”,
  3. Ceramic Material Systems: in Architecture and Interior Design, 2015,
Exploring Color Measurement Methods for Fiber Cement Siding
fiber cement siding
Appropriate color measurement tests can help you create fiber cement siding that is as beautiful as it is durable. Image Source: Shutterstock user Kiattisak Thongtawee

Fiber cement siding—a sturdy combination of wood pulp, fly ash, portland cement, and water—was first introduced in the construction industry just 25 years ago.1 Since then, it’s become one of the most popular materials that architects use for their projects. Almost 15 percent of all new homes have fiber cement siding, in part because this material is so durable and versatile. Although this material can be made to look just like brick, stone, or wood siding, it is actually far stronger than wood or vinyl materials, and less expensive to make than brick or stone. Quality fiber cement siding is fire resistant, termite-proof, rot-proof, and can withstand extreme weather conditions like heavy rain, strong winds or fluctuations in temperature.

But in order to achieve both the durability and beauty of fiber cement siding, manufacturers have to use appropriate color measurement methods at different points in the manufacturing process. Siding color is often the first thing that visitors notice when they look at a house, which is why it’s so important to test for color accuracy before you sell your products to customers. Even subtle inconsistencies in color could make fiber cement siding appear cheaply-made or weather-worn, and will negatively impact the overall appearance of the house. By using spectrophotometric color measurement during manufacturing, you can ensure that every piece of fiber cement siding meets your exacting standards and that your final product will appear beautifully-crafted.

fiber cement siding
Unpainted fiber cement siding is usually light grey in color. Image Source: Wikimedia user Michael Holley

Why Color Consistency Matters

Fiber cement manufacturers have two choices when they craft their materials: they can either paint the final products themselves or sell their customers the unpainted, unstained siding material.2 Regardless of which option you choose, you need to have accurate color measurement methods in place.

Unpainted fiber cement siding is usually light grey in color. If you offer your customers an unpainted, unstained product, you have to ensure that your products are the same standard shade of grey from batch-to-batch. That’s because your customers need a consistent base on which they can apply their final paint or stain color of choice. If the color of your unpainted siding varies batch-by-batch from light grey to dark grey, then the final coat of paint that your customers apply may appear darker or lighter than expected. To ensure that your customers can create the look they want, they must have a reliable blank slate.

Color consistency is also essential if you offer your customers pre-painted, installation-ready products. You have to ensure that every panel is the same color, as even small variations in paint or stain color could make the final siding project appear less aesthetically pleasing. Using a spectrophotometer, you can attain accurate color measurements for every product you make, whether it’s painted or unpainted.

fiber cement siding
By measuring color in advance, you can ensure that your final product looks consistent when it is installed by architects. Image Source: Shutterstock user Cory A Ulrich

Color Measurement Options

Siding can present special challenges for accurate color measurement and the best measurement method will depend on your manufacturing needs and preferences.

  • Directional 45°/0° Instrumentation: A directional 45°/0° spectrophotometer measures color the way the human eye sees it. Because it measures only diffuse reflectance and excludes specular information, it will automatically exclude the effects of attributes like gloss and texture. As such, you to easily match the appearance of samples with different geometric attributes.
  • On-line Instrumentation: 45°/0° and d/8° instruments are typically available in portable or benchtop formats, which require operators to physically measure samples at regular intervals. This can be a laborious process that introduces the possibility of operator error and leaves you unsure of whether the sample was truly reflective of the entire batch. On-line instruments like HunterLab’s SpectraTrend HT, on the other hand, eliminate these vulnerabilities.

The SpectraTrend HT uses a 0°/30° design and can be integrated within the manufacturing line to provide continuous non-contact monitoring without the need for manual sampling. Embedded lasers analyze the height of your sample, and sophisticated algorithms compensate for any texture variation, ensuring accurate and precise readings of every batch. However, the SpectraTrend HT doesn’t just report color data, it also analyzes whether that data falls within your tolerance range and instantly alerts operators to unwanted color variation. As such, you can easily identify out of spec product and take early corrective action. For many siding manufacturers, on-line instruments like the SpectraTrend HT are an essential part of optimizing both color quality control and overall efficiency.

HunterLab Reliability

For more than 60 years, HunterLab has worked with manufacturers in the construction industry to produce the most functionally reliable and aesthetically pleasing materials for houses, office buildings, and large-scale architectural projects. Our instruments offer the accuracy, precision, and flexibility manufacturers need in order to create the highest quality products. With a comprehensive range of spectrophotometers to choose from, you’ll be sure to find the right tools for your needs. Contact us today to learn more about our innovative technologies and world-class customer support services.

  1. “All About Fiber Cement Siding”,
  2. “How Long Does Fiber Cement Siding Last?”, December 18, 2015,
Spectrophotometric Color Measurement Helps Perfect Tar Paper or Roofing Felt
tar paper
Tar paper and roofing felt help protect a building’s wooden frame from water damage. Image Source: Creative Commons user U.S. Marine Corps

When a contractor is building a structure from scratch, they have to ensure that the wooden frame is well-protected at all times. Just one afternoon of heavy rainfall could cause significant water damage and may even make the building more prone to rot, leaks, and mold in the future. This is why many contractors use tar paper or roofing felt to add an extra layer of protection to a structure. In fact, this construction material is a requirement under many building codes around the country.1 High-quality tar paper and felt is waterproof, which protects the building from environmental damage over time. And, in some cases, the paper may also improve the appearance of a building’s roof. The product provides a smooth, even base for the shingles to adhere to, allowing them to lay perfectly flush against the surface.

Because tar paper and felt are the base on which shingles and siding materials are later applied, product consistency is absolutely essential. Not only does the texture and thickness of the product have to be exact from roll-to-roll in order to provide an even base layer, color quality control is also important to facilitate correct markings and measurements. When you use a spectrophotometer to test your tar paper or roofing felt during the manufacturing process, you ensure color consistency in every roll.

tar paper
If tar paper isn’t consistent in color, it can be difficult for contractors to make accurate measurements. Image Source: Flickr user Stone Soup Institute

Achieving Color Consistency in Tar Paper or Roofing Felt

Color consistency is important in tar paper and felt and can vary in based on the types of materials you use to create your products and how much asphalt you impregnate into the raw materials. Tar paper is either made with fiberglass or cotton rag scraps, which are then dipped in a thin layer of tar.2 Likewise, roofing felt is made from wood pulp products like cardboard and sawdust, which are soaked in a layer of thinned liquid asphalt. In both of these products, the addition of tar or asphalt causes the product to turn black. Generally, the more tar or asphalt you add to the material, the darker and heavier the final product will be.

This means that the color of your product may vary slightly if you add too much or too little asphalt or tar to the mix. Using a spectrophotometer, you can detect slight variations in color between one roll and the next, which may help you identify certain manufacturing inconsistencies, such as adding too much asphalt into the mix. If you add too much asphalt, then your product may be heavier than expected, which could make it difficult to install for certain uses, such as siding protection. And, if your product has too little asphalt in the mix, then it may be too lightweight, making it difficult to keep the product in place when it’s applied to rooftops.

Color consistency is also important for your customers. Tar paper and roofing felt are flexible, making it easy for contractors to maneuver pieces of it around uneven rooftops. But in order to ensure that the paper or felt rests flush against the roof and that each piece is cut to the roof’s exact measurements, contractors need to make chalk markings directly onto the tar paper or felt.3 Products that are one solid shade of black are easier to measure and mark because contractors can clearly see their markings against the background. If your product has areas of patchiness, or appears too grey in color, then it may be harder for contractors to see their measurements. Spectrophotometers can help you set a standard color for your products and ensure that each roll falls within that specified tolerance.

tar paper
Contractors make markings on tar paper using chalk or markers. A rich black background allows them to easily see their markings and make accurate measurements. Image Source: Creative Commons user U.S. Marine Corps

The Benefits of On-Line Color Measurement Instruments

The color measurement instrument you choose will ultimately depend on your manufacturing needs. One option is to install on-line instrumentation directly into your manufacturing line. By integrating a color measurement system like this into your line, you eliminate some of the challenges associated with portable or benchtop spectrophotometers.

Portable and benchtop instruments require operators to manually measure each sample of tar paper or felt at precise intervals. Not only can this process be time-consuming, it also leaves room for human error and your sample may not accurately represent the entire batch of product. For instance, if just one small sample of your tar paper is discolored, but the rest of the batch falls within tolerance, then you may throw away yards of high-quality product by mistake. Continuous non-contact monitoring eliminates the need for manual sampling, making the color measurement process more seamless and ensuring that the entire batch is analyzed.

HunterLab’s SpectraTrend HT is one of the most advanced on-line instruments available, using also uses 0°/30° geometry to measure color and while integrated height measurement accounts for texture variation to ensure the highest degree of accuracy. The SpectraTrend HT continuously analyzes the color of your products and instantly alerts you if a sample falls outside of your predetermined tolerance range, allowing you to quarantine defective product and take swift corrective action. With tools like this at your disposal, you can achieve greater color quality for every product that you create.

HunterLab Solutions

HunterLab has decades of experience in the building and construction industries, helping manufacturers create high-quality, aesthetically-pleasing, and functional materials. Whether you’re creating waterproof tar paper, cement materials, architectural glass or fiberglass roof shingles, we can help you find the best instrument for your needs. Contact us today to find out more about how spectrophotometry can improve your manufacturing process and allow you to realize your vision.

  1. “The Purpose of Roofing Felt”,
  2. “Why Do I Need Roofing Felt?”,
  3. “Tar Paper”,
Spectrophotometers Help Cosmetic Brands Create More Diverse Foundation Shades
foundation shades
Cosmetics brands are fostering inclusivity by offering a wider range of shades for all skin tones. Image source: Pexels user Gumzito Leruo

The cosmetics industry is changing at a rapid pace. In the past, it was nearly impossible for people of color to find the perfect shade of foundation for their skin tones, as most cosmetics brands only offered a handful of darker shade options. For instance, one cosmetics brand famously claimed to offer 30 different foundation shades, but only five of those shades were marketed toward people of color.1 Today, we’re seeing a significant shift in shade offerings from top makeup manufacturers and the emergence of exciting new brands building their reputations on their diverse palettes. Rihanna’s Fenty Beauty, for example, recently released a 40-shade collection of foundations that cover a massive range of skin tones, and nearly half of those shades are marketed toward people of color. As Marissa Muller writes in W Magazine, the move is regarded by many in the beauty industry as  “ushering in a new era of inclusivity.”2

As the need for inclusivity becomes more apparent, many cosmetics brands are creating broader spectrums of foundation colors in order to better meet their customers’ needs. However, to consistently create a diverse array of shades, you need to implement strict color quality control protocols based on spectrophotometric color measurement.

Why Color Matching is Important

Because foundation is meant to mimic a customer’s natural skin tone, precise color formulation and consistency matters. Even slight variations in color could make the foundation appear either too light or too dark for someone’s natural skin. People of color who have darker skin tones often find color matching particularly difficult, as many foundation shades make their skin appear grey or ashy. This happens when a foundation is too light in color or too opaque—it doesn’t blend in seamlessly with the skin’s natural undertones and this is especially apparent on darker skin.3

Due to the difficult process of finding the perfect match, customers generally like to stick with the same foundation brand once they find a shade that works well with their skin. In fact, a recent Corra Research study found that only 11 percent of makeup wearers switch foundation brands frequently and customers were significantly less likely to switch if they found products that closely matched their skin color.4 As such, offering a wide range of shades that will blend with a diverse array of skin tones will help you meet the needs of your customers today and likely for years to come.

foundation shades
The more foundation shades a manufacturer creates, the more likely one of the shades will match a customer’s skin tone. Image source: Wikimedia user Jen

The Challenges of Creating A More Inclusive Palette

One of the biggest challenges that cosmetics brands face when they create a larger number of foundation shades is that differences between the shades will naturally be more subtle compared to a smaller collection of shades, making distinctions between shades less apparent to the human viewer. In a 10-shade collection, for instance, the difference between the darkest and second-darkest shade available will likely be obvious to the naked eye. In a 50-shade collection, the difference between the darkest shade and the second-darkest will likely be far less obvious.

The color variation between shades depends on the amount of pigment used to create the foundation. Most foundation manufacturers use varying amounts of titanium dioxide or iron oxide pigments to make different colors of foundation.5 The more pigment that a foundation has in the mix, the darker the final color will be. If you have a lot of color variation between one shade and the next-closest shade, then you likely used a higher percentage of pigment in the darker shade’s mix than you did in the lighter shade. However, if you want to create a more inclusive product range that matches a wide range of skin tones, then the amount of pigment that you use will likely only change by a percentage or two between each shade, perhaps even less. For instance, the darkest shade in your collection may contain 15 percent pigment, and the next-darkest shade may contain 14.5 percent pigment—a difference of just half a percentage.

This small change in pigment is far too subtle for the human eye to easily detect on its own, but it can make a significant difference once the product is applied to the skin. As such, if you only rely on visual assessment of your product’s color, then both the formulation and manufacturing processes may be compromised. A spectrophotometer is therefore necessary to facilitate formulation and ensure that future products remain consistent batch-to-batch.

foundation shades
Spectrophotometers can help you ensure that every foundation in your shade range is consistent from product-to-product. Image source: Pexels user Beata Dudova

The Benefits of Spectrophotometric Color Measurement

Spectrophotometers are designed to see color the way the human eye sees it, only better. By distilling color to numerical data, spectrophotometers quantify each foundation shade and can detect even the most subtle differences between shades. As such, these sophisticated color measurement instruments take the guesswork out of the formulation process, showing you exactly what color the resulting shade is and determining whether your product falls within the tolerance you specify. With color measurement software already built into each instrument, you can decide exactly how much color variation you want between one shade and the next, allowing you to more precisely tailor your palette to your needs.

Not only can spectrophotometers help you determine how much pigment to mix into your final formulation, they are also invaluable for ensuring consistent batch-to-batch production of your foundations. Whether you are working with liquid or powder products, integrating spectrophotometric color measurement in the manufacturing process allows you monitor your foundations at critical points of production. By doing so, operators can detect unwanted color variation as early as possible, allowing them to take swift corrective action and prevent the release of inaccurately pigmented products. When a brand is building relationships with customers based on its ability to create accurate color matches, this level of quality control is essential.

HunterLab Innovation

HunterLab has been a leader in color measurement for over 60 years. Today, we combine cutting-edge technologies with user-friendly designs to create versatile, innovative, and reliable spectrophotometers that help our customers take color quality control to the highest level. With advanced color measurement algorithms, integrated software, and state-of-the-art hardware in every instrument, our spectrophotometers are essential tools for cosmetics manufacturers looking to create the best products possible. Contact us to learn more about our renowned instruments, customizable software packages, and world-class customer support services.

  1. “Makeup That Addresses the Many Shades of Women”, March 19, 2014,
  2. “How Rihanna’s Fenty Beauty is Ushering in a New Era of Inclusivity in the Beauty Industry”, September 19, 2017,
  3. “Here’s Why Your Foundation Looks Grey”,
  4. “Beauty Product Loyalty”,
  5. “Anatomy of Liquid Foundations”, October 9, 2013,
Spectrophotometric Color Measurement Enhances Traffic Sign Visibility and Protects Public Safety
traffic sign color
Color measurement accuracy is important for traffic signs because drivers need to quickly see information while traveling at fast speeds. Image Source: MaxPixel user Nikon D90

No matter where you are in the world, the color of a traffic sign can instantly tell you roughly what that sign means, even if you’re unable to read the symbols and text written on it.1 Seeing a flash of red on the side of the road up ahead almost always signals to the driver that a full stop is coming up. Meanwhile, a green sign tells you to proceed; a yellow sign tells you to slow down; an orange sign urges extreme caution; and blue signs tell you where you are. Nearly every sign in the world adheres to the same basic color language so that drivers can easily follow the rules and stay safe on the road.

Yet in order for these color rules to translate across languages and countries, traffic sign manufacturers need to ensure color measurement accuracy for every sign they install. Failure to accurately match the color of the sign to the official standard set by transportation departments could result in confusion for drivers, and even potential road accidents. To prevent these issues and ensure that transportation departments can always turn to you for the most accurate, reliable traffic signs, you need to invest in a spectrophotometer that is capable of measuring sign color with a great degree of accuracy.

traffic sign color
The reflective nature of some traffic signs can make it difficult to accurately measure color. Image Source: Unsplash user Kyle Glenn

Spectrophotometers Ensure Accurate Traffic Sign Coloration

A stop sign is usually a shade of deep tomato red, whereas an orange sign placed next to a construction zone will be far brighter, and nearly fluorescent, in color. When colored correctly, these two signs look very different from one another. However, if the red colors that you use to make your signs lean too heavily toward the orange end of the color scale, drivers may mistake the sign for a caution symbol, rather than a full stop. Similarly, orange construction signs that appear too deep red in color may look like stop signs when, in fact, drivers merely need to slow down. Incorrect variations in sign color could dramatically impact how drivers perceive a traffic sign, causing confusion, and sometimes resulting in unnecessary traffic congestion or accidents.

Using modern color measurement technologies like spectrophotometers in your production process can prevent these problems. Spectrophotometers create an objective basis for color analysis that avoids the inherent subjectivity of vision-based assessment. This is because there are biological differences in human color vision that may impact how color is perceived; one person’s idea of orange may appear more red to another person. Inconsistent lighting conditions and variations in background color can also affect color perception—a dark background may make an orange sign appear more bright and fluorescent than if you viewed the same color against a light, or white, background. The level of color contrast tricks the human eye.

Additionally, the human eye innately struggles to differentiate between colors that are close together on a standard color wheel, like orange and red. Orange shades fall in a wavelength between 585 and 620 nanometers, whereas red shades fall between 630 and 740 nanometers.2 It can be all but impossible for the human eye to accurately detect the difference between an orange shade approaching 620 nanometers compared to a red shade in the 630 nanometer range. Using a spectrophotometer, you can measure obtain accurate numerical coordinates for each color to determine whether the color of your sign meets your color standard. In other words, you can guarantee that your orange signs will be true oranges, and your red signs will be true reds.

Analyzing Reflective Surfaces

One of the challenges associated with measurement of traffic sign color is that some signs are designed to be reflective. This is essential for allowing drivers to see them even at night. However, without the right spectrophotometer for your needs, it can be more difficult to obtain the data you need from these materials, as the reflected light could make the signs appear lighter in color than they actually are. HunterLab’s 45/0 geometry is accepted as the best to use to measure retroreflective material.

traffic sign color
Tools like spectrophotometers can help you create consistent signs and earn the trust of safety departments around the world. Image Source: MaxPixel user Canon EOS 550d

Analyzing the Durability of Traffic Sign Color

Another challenge that traffic sign manufacturers face is that paint or other colored materials can fade over time, which will negatively impact how the signs are perceived by drivers. For example, studies have found that after just one or two years on the road, stop signs have a great degree of variability in retroreflectivity and color depending on the quality of the materials used.3 On average, most stop signs made with quality reflective materials and colors could last about 10 years in the field without requiring repairs or replacements. This means that, in order to meet department of transportation expectations, you should test that your signs can withstand the elements and last for a minimum of 10 years.

While you won’t be able to wait 10 years to test whether the color of your signs stays true, you can use a spectrophotometer to test your signs for initial durability after being exposed to the elements or employ artificial aging environments to simulate prolonged exposure to stressors. A portable spectrophotometer can help you test samples of your signs outdoors or in artificial environments, allowing you to see whether premature color fading occurs. If the longevity of your signs is determined to be inadequate, you can use this information to improve your manufacturing methods and enhance durability.

HunterLab Accuracy

In the traffic sign industry, trust and reliability are absolutely essential. Because traffic signs are vital tools for keeping drivers safe on the road, traffic sign manufacturers need reliable color measurement methods to optimize the performance of their products. For more than 60 years, HunterLab has provided the highest quality spectrophotometers on the market for manufacturers in the safety industry. Our tools are capable of quantifying color with the highest degree of accuracy, ensuring that every traffic sign meets the exacting standards set by transportation departments around the world. Contact us today to find out more about our innovative technologies and let us help you select the perfect instrument for your company’s needs.


  1. “How to Read Traffic Signs”, July 4, 2012,
  2. “Shades of Orange”,
  3. “Traffic Sign Life Expectancy”,
Color Consistency in Art Papers Helps Paper Manufacturers Meet the Needs of Printmakers
art papers
Accurate color measurement tools can help you test your paper for color and consistency, resulting in a higher-quality final product. Image source: Pexels user Tim Gouw

While visiting a friend’s home, I noticed an enormous, beautiful painting hanging above the fireplace. Up close, I could see what looked like real paint clinging to the surface of the paper and assumed that I was looking at the original work of art. But when I asked my friend who painted the piece, she responded, “Oh, that’s actually a print! The artist was selling three of them just like it.”

Even if you can’t afford a $179 million Picasso, you can still get an excellent copy of that same painting for as little as a few hundred dollars, often much less.1. Yet not all art prints are worth hanging on your walls. The quality of the print paper has a huge impact on the appearance of the final piece; the color, opacity, and texture of the paper all affect how the inks and paints will appear once printed onto the final product. Color measurement tools can be used by paper manufacturers to ensure that each blank sheet of paper will allow printmakers to produce their ideal images.

art papers
Reproductions of famous art pieces should be printed on paper that will make the colors appear most like the original. Image source: Wikimedia Katsushika Hokusai

Why the Color of Art Papers Matters

All papers can affect the final appearance of art prints; CMYK inks, for example, will look warmer when they are printed on cream-colored paper, whereas they will appear cooler in tone when printed on paper that leans more toward the blue end of the scale. Color discrepancies become even more apparent on darker-colored papers; generally, the richer and darker the paper is, the more it will impact the final look of the ink on the art print.2 As such, printmakers must carefully consider the specific interactions between materials in order to produce their desired colors and seek out the papers that will allow them to create their ideal hues.

Printmakers place a great degree of trust in the paper manufacturing industry because the quality of their product depends on a harmonious marriage between pigment and paper. If printmakers see a sample of a particular sheet of colored paper, then they expect that their future paper order will match that color exactly. Any small variation in hue or color consistency could cause art printmakers to lose trust in your paper products, as such variation can interfere with your customer’s ability to create the images they want. For example, a paper with too much yellow can make blue tones appear more teal or green than the printmaker intends, compromising the integrity of the image. Imagine van Gogh’s “Starry Night,” but with a dull green sky, rather than a rich navy blue.

art papers
Original paintings have fine brushstroke details that are difficult to show in a copied print. Image source: Pixabay user BonnieHenderson

The Value of Spectrophotometric Color Measurement

Regardless of which type of paper you manufacture, from slick, coated poster paper used for mass-produced reproduction prints to heavily textured products popular for limited-edition fine art prints, a spectrophotometer is an essential tool for creating papers that meet the needs of your customers. A spectrophotometer gives you extraordinary insight into the color of your papers, allowing you to perfect your processing methods and ensure consistent, accurate coloration. These versatile instruments can be integrated at various critical parts in your manufacturing process as well as used to evaluate the behavior of your products post-manufacturing, creating an end-to-end color quality control system.

Paper manufacturing involves a wide variety of materials and processes that can impact the final appearance of your products, and monitoring color throughout can help you maintain your ideal hues. Factors that impact color include coatings, sizing, and the dyes, brightening agents, or other colorant additives that you use to color your paper. By performing a spectrophotometric evaluation of the paper color during each applicable step in your manufacturing process, you can analyze whether your paper conforms to color expectations, or if you notice any inconsistencies. By instantly alerting you to unwanted color variation, spectrophotometers allow you to take early corrective action, optimizing production efficiency.

Once you’ve ensured that your paper is consistent in color upon production, you must also test for color stability. When it comes to making quality art prints, the color of the paper needs to be stable in color over time in order to preserve the integrity of the artwork, particularly for those customers seeking archival quality.3 An art print will likely hang on someone’s wall for years, perhaps even decades, and as such, it needs to maintain correct coloration even when exposed to environmental stressors like UV radiation, humidity, and heat. To ensure that your paper can withstand these stressors, you may expose a sample of the paper to an artificial aging environment, then measure the impact on color stability and determine whether reformulation is necessary to optimize durability. For example, these tests may alert you to improper lignin removal, allowing you to modify your processing methods to improve color stability and ensure that your customers will be able to use your papers as intended.

HunterLab Reliability

HunterLab has been a pioneer in the field of color measurement for over 60 years. Today, we offer a comprehensive line-up of spectrophotometers ideally suited for our customers in the paper industry. Our state-of-the-art instruments and customizable color measurement software packages provide our clients with the highest degree of insight into their products, allowing for meticulous color consistency. Contact us to learn more about how HunterLab spectrophotometers can enhance your paper production process.

  1. “Picasso Painting Fetches $179 Million at Auction”, May 11, 2015,
  2. “Dare to Print on Colored Paper Stock”, January 17, 2007,
  3. “A Consumer Guide to Traditional and Digital Print Stability”,
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