CCE CCE Color Measurement & Instrumentation 2 — Questions and Answers
Question 1: In colorimetry, what does the term 'metamerism' describe?
- Colors that look identical under all light sources
- Two colors that match under one illuminant but differ under another (Correct answer)
- The tendency of pigments to fade over time
- The process of converting RGB to CMYK
Correct answer: Two colors that match under one illuminant but differ under another
Metamerism occurs when two colors with different spectral compositions appear identical under one illuminant but differ under another.
Question 2: Which CIE standard illuminant is the international standard for color evaluation in graphic arts and proofing environments?
- Illuminant A
- Illuminant C
- Illuminant D50 (Correct answer)
- Illuminant F2
Correct answer: Illuminant D50
CIE Illuminant D50 approximates 5000K daylight and is the standard illuminant used in graphic arts for color viewing and proofing.
Question 3: According to ISO 12647, what ΔE tolerance is considered acceptable for color matches in commercial printing?
- ΔE < 1
- ΔE < 2 (Correct answer)
- ΔE < 5
- ΔE < 10
Correct answer: ΔE < 2
ISO 12647 specifies that a ΔE of less than 2 (using ΔE 2000) is the acceptable tolerance for color matches in commercial printing.
Question 4: A spectrophotometer reading gives L*=50, a*=0, b*=0. What color does this represent?
- Pure white
- Pure black
- A neutral mid-tone gray (Correct answer)
- A saturated red
Correct answer: A neutral mid-tone gray
In CIE L*a*b*, L*=50 indicates medium lightness, and a*=0, b*=0 indicates no chroma, resulting in a neutral gray.
Question 5: Which proprietary color formula system uses a numbered fan guide to specify spot colors in graphic arts and printing?
- Munsell
- CIE XYZ
- Pantone Matching System (Correct answer)
- RAL
Correct answer: Pantone Matching System
The Pantone Matching System (PMS) is the industry-standard system for specifying and communicating spot colors in graphic arts and commercial printing.
Question 6: What does a colorimeter primarily measure, in contrast to a spectrophotometer?
- The spectral power distribution of a light source
- Tristimulus values using three broadband filters (Correct answer)
- Ink density at a single wavelength
- The color rendering index of light sources
Correct answer: Tristimulus values using three broadband filters
A colorimeter uses three broadband filters corresponding to X, Y, Z tristimulus values to measure color, while a spectrophotometer captures full spectral data.
CCE CCE Color Measurement & Instrumentation 2
In colorimetry, what does the term 'metamerism' describe?