HDR Calibration & Display Measurement 1 — Questions and Answers
Question 1: What unit is most commonly used to express peak luminance in HDR display specifications?
- Lux
- Nits (cd/m²) (Correct answer)
- Lumens
- Foot-lamberts
Correct answer: Nits (cd/m²)
Nits (candelas per square meter, cd/m²) is the standard unit for measuring display luminance in HDR specifications.
Question 2: What does MaxCLL represent in HDR static metadata?
- The average luminance across all frames
- The luminance of the brightest single pixel anywhere in the content (Correct answer)
- The maximum luminance of the mastering display
- The maximum chroma level across all frames
Correct answer: The luminance of the brightest single pixel anywhere in the content
MaxCLL (Maximum Content Light Level) specifies the luminance of the single brightest pixel across the entire video content.
Question 3: Which instrument provides the highest accuracy for measuring spectral output during professional HDR display calibration?
- Colorimeter
- Spectrophotometer
- Spectroradiometer (Correct answer)
- Photometer
Correct answer: Spectroradiometer
A spectroradiometer measures the full spectral power distribution emitted by a display, providing the highest accuracy and avoiding the filter metamerism errors that can affect colorimeters.
Question 4: What is the standard peak luminance target for professional HDR10 mastering?
- 400 cd/m²
- 600 cd/m²
- 1,000 cd/m² (Correct answer)
- 4,000 cd/m²
Correct answer: 1,000 cd/m²
HDR10 mastering is standardized at 1,000 cd/m² peak luminance, as established by industry standards for professional content creation workflows.
Question 5: What does MaxFALL represent in HDR content metadata?
- The maximum backlight luminance of the mastering display
- The average of all peak luminance values across all frames
- The highest frame-average luminance value across the entire content (Correct answer)
- The maximum allowable luminance in any 1-second segment
Correct answer: The highest frame-average luminance value across the entire content
MaxFALL (Maximum Frame Average Light Level) is derived by averaging all pixel luminance values within each frame and then taking the maximum of those per-frame averages across the full program.
Question 6: Which SMPTE standard defines the static metadata that describes mastering display color volume for HDR content?
- SMPTE ST 2048
- SMPTE ST 2084
- SMPTE ST 2086 (Correct answer)
- SMPTE ST 2094
Correct answer: SMPTE ST 2086
SMPTE ST 2086 specifies the mastering display color volume metadata, including the chromaticity coordinates of primaries, white point, and minimum/maximum luminance of the mastering monitor.
Question 7: What is the approximate minimum luminance specification of a top-tier professional HDR mastering monitor?
- 0.05 cd/m²
- 0.005 cd/m²
- 0.0005 cd/m² (Correct answer)
- 0.00005 cd/m²
Correct answer: 0.0005 cd/m²
High-end professional HDR mastering monitors achieve minimum luminance of approximately 0.0005 cd/m² or lower, enabling contrast ratios exceeding 1,000,000:1.
HDR Calibration & Display Measurement 1
What unit is most commonly used to express peak luminance in HDR display specifications?