ISF HDR Standards & Tone Mapping 3

Question 1

In PQ (SMPTE ST 2084) calibration, what luminance level represents diffuse (reference) white?

Accepted Answer

203 nits

Answer

In PQ/HDR10 content, diffuse white is encoded at approximately 203 nits, providing luminance headroom above reference white for specular highlights.

Question 2

What is 'clipping' in the context of HDR tone mapping?

Accepted Answer

Loss of highlight detail when content luminance exceeds the display's peak capability

Answer

Clipping occurs when HDR content specifies a luminance level beyond what the display can output, causing bright highlights to be rendered without detail.

Question 3

What luminance value does code value 0 represent in SMPTE ST 2084 (PQ)?

Accepted Answer

0 nits (absolute black)

Answer

In ST 2084, code value 0 maps to 0 nits (absolute black), with the PQ curve providing perceptually uniform encoding all the way to this minimum.

Question 4

When evaluating HDR display performance for ISF calibration, which pair of measurements is most critical?

Accepted Answer

Both peak white and black level to calculate dynamic range

Answer

ISF HDR evaluation requires measuring both peak luminance and black level to fully characterize the display's dynamic range and native contrast ratio.

Question 5

What is the minimum peak luminance requirement for an LCD-type display to achieve UHD Alliance 'Ultra HD Premium' certification?

Accepted Answer

1,000 nits

Answer

The UHD Alliance requires LCD-based displays to reach at least 1,000 nits peak luminance with a black level at or below 0.05 nits for Ultra HD Premium certification.

(ISF) Imaging Science Foundation Certification Practice Test

(ISF) Imaging Science Foundation Certification Practice Test

ISF HDR Standards & Tone Mapping 3