So, a light source that is 3000 K and 90 CRI might<\/em> have one of the three color rendering properties described by this manufacturer, and other versions of 3000 K and 90 CRI could<\/em> have the other characteristics, but the numbers presented don\u2019t describe or confirm those properties or characteristics at all<\/u>.\u00a0 For that we need to look at TM-30 and beyond.<\/p>\n Two of the three descriptions reference the color rendering of white, but there\u2019s no explanation of how this is determined, and that\u2019s a problem.\u00a0 Neither CRI nor TM-30 specifically evaluate white surfaces or materials.\u00a0 There have been several whiteness metrics proposed over the years, beginning in the 1930s.\u00a0 As far as I know, only one has been adopted by a standards setting organization (the CIE whiteness formula from 1986).\u00a0 However, this manufacturer can\u2019t be using the CIE formula because it only uses D65 (a standardized spectra at 6500 K) and the LEDs here are all 3000 K.<\/p>\n Neither CRI nor TM-30\u2019s R<\/em>f<\/sub> (the fidelity index) say anything about the impact of the spectrum on specific color ranges, such as warm colors.\u00a0 R<\/em>g<\/sub> doesn\u2019t either since it gives us an average shift in saturation across all 99 color samples.\u00a0 To see what color ranges are affected, and how, we need to look at the local hue and chroma shifts (\u201clocal\u201d meaning the color samples falling within each of the 16 hue bins shown in the Color Vector Graphic or CVG).\u00a0 As shown below, a TM-30 intermediate report gives us the CVG and bar graphs of the hue shift (R<\/em>hs<\/sub>) and chroma shift (R<\/em>cs<\/sub>) for each hue bin.\u00a0 The bar graph information is included in the Color Vector Graphic, of course, but some may find the bar graphs easier to read.<\/p>\n So, if the question is, \u201cWhat colors are enhanced by this spectrum?\u201d, and if \u201cenhanced\u201d means made more vivid, the answer is found in the chroma shift bar graph.\u00a0 For any spectra, the color ranges that have a positive chroma shift would be enhanced, while those with a negative chroma shift might be described as being muted, dulled, or grayed.\u00a0 This is true regardless of the material because color rendering is about an object\u2019s color, not its material composition.\u00a0 \u201cTextiles and darker accents\u201d don\u2019t describe a color range, so there\u2019s no way of knowing the impact of a spectra on those materials without also knowing their color.\u00a0 As with whiteness, though, the manufacturer gives us no detailed information, just assurances that these lights are great.<\/p>\n Proceed with caution.\u00a0 Don\u2019t accept any of these claims without proof.\u00a0 Get your lighting reps to bring you samples to evaluate before specifying these products. CCT and CRI cannot explain and back up a claim about a light source\u2019s impact on the appearance of specific color ranges and white materials.\u00a0 To do so, a manufacturer should provide specifiers with a description of the impact, a TM-30 report that supports that claim, and perhaps additional metrics for claims that can\u2019t be verified or validated with TM-30.<\/p>\n","protected":false},"excerpt":{"rendered":"![\"TM-30](\"https:\/\/designinglight.com\/wp-content\/uploads\/2026\/08\/Intermediate-Report.png\")