ASTM D1729

Introducing ASTM D1729 – Industrial Physics

ASTM D1729 is an ASTM international standard specification for the visual assessment of colors and color differences of diffusely illuminated opaque materials.  

It’s an ASTM approach that specifies the equipment and procedures needed for the color matching inspection. It’s a color measuring observation that requires judgments by observers with, at least, a minimum of normal color vision. 

When you are inspecting the color and color differences of materials such as metallic and pearlescent paints you’ll need strong illumination. Illumination that’s close to being a geometric simulation of direct sunlight. This is because directional illumination enables you to observe the sparkle (glitter) and goniochromatism of such materials. 

The ASTM D1729 process

It’s common to use a color measuring instrument when testing to ASTM D1729 standards, but color matches can also be checked visually. The standardization of visual examination has greatly improved the uniformity of products and the accuracy of color matches. 

As well as critical color matching the ASTM D1729 approach can help you to choose or approve of a color. This practice is widely used in industry to: 

• Choose colors 
• Exhibit a color’s reproducibility 
• Inspect incoming materials 
• Monitor color producing processes 
• Inspect finished goods 

A visual color testing appraisal is important when the product inspected is not of the same material as the color standard to which it’s compared. 

Observing ASTM D1729 tests 

It’s assumed that the observer in the ASTM D1729 test has superior color vision and is trained and experienced in observing and classifying color differences. Thankfully, within ASTM E1499 you’ll find guidance on the selection, evaluation, and training of observers. 

The lighting of the experiment should simulate average daylight. It’s recommended that you use the illuminant D65 CIE standard. It’s a commonly used standard illuminant defined by the International Commission on Illumination (CIE). 

ASTM D1729 testing equipment

So, how can Industrial Physics improve your ASTM D1729 testing?  

TQC Sheen Colorbox – illuminated assessment cabinets

Our illumination test cabinets are built for accurate color assessment and they’re ideal for ASTM D1729 testing. Use a colorbox to inspect and color match inks, paints, plastics, cosmetics, textiles, knitwear, food, paper, colorants, and other coloured materials. 

TQC colorboxes offer a range of illumination conditions for any visual inspection. The multiple, selectable light sources allow assessment of gloss, structure, damages and metamerism.  

Our colorboxes are available in 60 and 120 cm wide models. They’re supplied with removable viewing tables and runtime counters and are finished to the highest quality standards.  

Your global test and measurement partner for ASTM D1729