Guide to Color Spectrophotometers: What Tool Is Right for Your Application?

Consumers interpret color consistency as a hallmark of your company's quality and goods' desirability. As a result, color measurement is a critical process in manufacturing across many industries, from food production to plastics and textiles. Spectrophotometers outperform manual comparisons by delivering objective and scientific data that eliminates guesswork and supports consistency. Learning how to choose the right spectrophotometer for your needs helps ensure the most accurate data capture and best value for your investment.

1. Use Your Sample Characteristics as Your Primary Guidance

Modern spectrophotometry is entirely substrate-driven, with specialized solutions available to measure color precisely in samples like tomato products and coffees. As a result, the traits of what you're quantifying color and spectral data in are the bedrock for choosing the right spectrophotometer. Factors to consider include:

Sample Opacity

Spectrophotometers use different measurement geometries and construction designs based on a sample's opacity. 

For example, manufacturers generally measure translucent and transparent samples by capturing transmission data. In this design, light passes through the sample to the detectors on the other side, which collect and analyze the data based on the chosen color scale or index.

Conversely, reflectance measurements are ideal for translucent to opaque samples with nonuniform characteristics, like snack foods. These options can feature either directional or diffuse geometries. 

Directional 45°/0° and 0°/45° spectrophotometers replicate the way human eyes perceive color with either bidirectional or circumferential light source configurations. This approach is best for ensuring color consistency in samples where surface finishes may vary and impact color perception. Diffuse 8° spectrophotometers equally illuminate from all directions with a spherical light source design, making them perfect for applications whose goal is true color match. These solutions are also compatible with transmittance measurement for translucent and transparent samples, boosting their application versatility.

Sample Cost and Size Requirements

When evaluating which spectrophotometer will most effectively meet your needs, the minimum and maximum sample sizes it can handle are a key consideration.

In industries like chemical processing and pharmaceutical manufacturing, samples can be extremely expensive. The ideal solution will offer the smallest possible sample size minimum to help contain costs. In contrast, some applications call for larger samples for increased measurement accuracy, so you'll want to choose a device with the flexibility to accommodate bigger substrate sizes.

Samples Requiring Simultaneous Data Capture

Quantifying data for other sample aspects like haze is critical to some products. For example, brewers must measure for color and turbidity to ensure consistent quality. Technologically advanced systems can simultaneously capture both measurements for improved efficiency. Similarly, more sophisticated equipment can also provide color and gloss data in a single operation.

2. Determine Where You Need to Measure

Equally as important as the samples you're measuring is where you're capturing that data. Spectrophotometers come in various styles to simplify the task based on your measuring location:

• On-the-spot solutions: If you regularly quantify data on the production floor or in a supplier's facility, portability is a must. Convenient hand-held devices enable you to take measurements in the field, preventing time loss and the logistics challenges of transporting samples elsewhere.
• Benchtop models: Compact benchtop spectrophotometers preserve valuable facility space by offering a comprehensive solution in a small footprint.
• In-line tools: In-line solutions are ideal for installation directly within production lines to provide real-time color and spectral data as goods travel between production or processing points.

3. Assess the Technical Specifications and Equipment Features

Aligning your needs with the technical details and optional features a spectrophotometer offers will help guide you to the best choice. Factors to assess here include:

Resolution and Range

Equipment resolution and wavelength ranges vary, which can help define the limitations and ideal applications for a spectrophotometer. For example, high-precision industries have much tighter color and spectral tolerances. These industries and applications require solutions that can provide accurate, high-resolution results and detect and report more spectral detail across a broader range.

Industry Standards Library

Ideally, the color science equipment you invest in will offer measurement against many widely accepted color indices and scales. Common ones to look for when comparing options include RGB, CMYK, CIE L*a*b*, and Hunter L, a, b.

Certain industries require measurements with specialized indices and scales to conform to standards. For example, those engaged in edible oil production must compare their products' color to standards established by the American Oil Chemists Society (AOCS) and the International Organization for Standardization (ISO). If similar standards apply to your industry, you'll want to verify the spectrophotometer has the required library for comparison.

Speed

Variable input expenses abound in today's most demanding industries, and many manufacturers have little control over the prices of the raw materials they rely on for production. As a result, finding other ways to optimize costs becomes instrumental to profitability. Boosting production efficiencies, reducing waste, and successfully launching new products are effective methods for maintaining and growing revenue. 

Fast color measurement contributes to those goals by enabling:

• Time savings: Innovative spectrophotometers simplify setup, measurement, and cleanup. User-friendly operation and quicker data capture mean investing less time in operator training and eliminating production bottlenecks. 
• Less waste: Assessing color at every production stage delivers transparency into when and how color changes at each one. Your facility gains insights into where possible challenges arise so you can intervene and prevent needless material waste.
• More successful product development: Early insights into manufacturing impacts on color are also vital in new product development. Fast data capture helps pinpoint issues before full-scale production, supporting higher-quality goods.

Integration With Existing Solutions

The best color measurement solutions will enhance what already works for your facility.

Complementing the data-capture application of a spectrophotometer is its ability to share that information for documentation. The need to export data means your device should be compatible with a range of other equipment, including printers, keyboards, and barcode readers. Features like USB ports and ethernet connectivity also simplify transferring data for Laboratory Informational Management Systems (LIMS) and Statistical Process Controls (SPCs).

Additionally, the best spectrophotometer for your needs should support the quality control and assurance frameworks you use throughout your facility. That means the tool should be agnostic about your methodology and seamlessly integrate with it.

Additional Features to Evaluate

While not inherently necessary to choosing the right spectrophotometer, there are several other features that can help narrow your choices or guide your decision:

• Intuitive operation: A device that's easy to use and offers intuitive operation will more readily appeal to your workforce.
• Customizability: The ability to choose between built-in conveniences and create your own color formulas and tolerances increases the equipment's versatility.
• Value: Spectrophotometers with low maintenance requirements and more features for the price point deliver a better value and long-term return on investment.
• Intelligence: Next-generation smart solutions include automation and intelligence to help future-proof color measurement processes.

Find the Right Color Measurement Solution at HunterLab

HunterLab develops and manufactures the most innovative and comprehensive color measurement solutions based on over 70 years of expertise in spectrophotometer uses and applications. Browse our entire selection of advanced equipment to find the best one for your needs, or contact us today for more details and product advice.