HDR (High Dynamic Range)

HDR (High Dynamic Range) is a family of imaging technologies that captures, processes and displays a wider range of luminance and color than the SDR (Standard Dynamic Range) Rec.709 standard. Where SDR is limited to about 100 nits peak brightness, HDR formats target 1,000 to 10,000 nits, revealing detail in highlights (sun, specular reflections, neon) and shadows simultaneously. HDR uses new transfer functions (PQ — Perceptual Quantizer, SMPTE ST 2084, and HLG — Hybrid Log Gamma, ITU-R BT.2100) instead of the gamma 2.4 of Rec.709, because traditional gamma cannot describe the extended luminance range. The dominant standards are: HDR10 (10-bit, static metadata), HDR10+ (dynamic metadata, royalty-free), Dolby Vision (12-bit with dynamic metadata, the cinema and premium streaming standard), and HLG (broadcast-friendly, no metadata required). HDR mastering requires reference monitors (Sony BVM-HX310, Canon DP-V series) capable of at least 1000 nits and P3-D65 or Rec.2020 gamut coverage. The grading session produces a master at the target peak luminance (typically 1000 nits for streaming, 4000 nits for premium), from which SDR trims are derived. Streaming platforms (Netflix, Apple TV+, Disney+) mandate Dolby Vision or HDR10 masters for tier-1 originals. Reference: ITU-R BT.2100 (HDR system parameters) and SMPTE ST 2084 (PQ).