In the printing industry — whether it’s rotogravure, flexographic, offset, or screen printing — color accuracy is very critical. Packaging converters, commercial printers, and brand owners demand consistent, high-quality colors across different jobs, substrates, and print runs. To achieve this, printers rely on spectrophotometers. But not all spectrophotometers are the same — one often-overlooked factor is the geometry. The two most common types are 45/0 (45-degree illumination, 0-degree viewing) and D/8 (diffuse illumination, 8-degree viewing). So, which geometry works best for your printing process?
Understanding 45/0 Geometry
In a 45/0 spectrophotometer, the light is directed at a 45-degree angle, and the detector captures reflected light at 0 degrees — simulating how the human eye perceives color. This setup is ideal for matte or smooth printed surfaces such as the uncoated paper or certain packaging films because it includes the surface appearance in the measurement.
However, on glossy printed substrates, it can be misleading. For example, if you measure two identical black samples one matte and one glossy — with a 45/0 device, the glossy one will appear darker and more saturated, even though the color is chemically the same. That’s because the detector picks up direct reflections from the glossy surface, affecting the result.
What Makes D/8 Geometry Different?
A D/8 spectrophotometer uses an integrating sphere to diffuse light evenly over the printed surface, with the detector capturing light at an 8-degree angle. It can operate in two modes:
• Specular Included (SCI) – Measures only the color, excluding surface gloss or texture.
• Specular Excluded (SCE) – Includes surface appearance in the result, similar to 45/0.
In SCI mode, a D/8 device will give nearly identical readings for glossy laminated packaging and the same design printed on a matte board. This makes it ideal for quality control, color formulation, and matching across different substrates in printing.
Which Geometry Should Paint Manufacturers Choose?
In printing, substrates and finishes change constantly — from high-gloss PET films in rotogravure to textured papers in screen printing. 45/0 spectrophotometer might show different results for the same color applied in matte vs glossy finishes causing unnecessary rework, color mismatches, and customer complaints.
That’s where D/8 geometry excels. It provides consistent and repeatable color measurements across various substrates with varying gloss levels, surface finishes and textures. Whether you’re measuring high-gloss, textured, or matte finishes, a D/8 spectrophotometer delivers consistent results. Its flexibility across different gloss levels and surface types makes it ideal not just for glossy or metallic finishes but also for standard matte finishes.
Its ability to measure across different finishes, special-effect inks, and substrates makes it the preferred choice for the printers aiming to achieve accurate color consistency in their printing process.
Conclusion
If your focus is purely on how the color appears visually on a single matte finish, 45/0 may be sufficient. But for precise, reproducible, and scalable color control across multiple substrates, print processes, and gloss levels, D/8 geometry is the more preferred choice for the printing industry.
