Color spaces in editing software such as Rec.709 (SDR), Rec.2020 (SDR), Rec.2100 HLG, and Rec.2100 PQ may seem complex, but they all refer to standards for Color Space and Dynamic Range. They directly affect the color representation, brightness range, and final display effect of your edited videos.
Let me explain their roles and differences one by one:
1️⃣ Rec.709 (SDR)
- ✅ Full Name: ITU-R Recommendation BT.709
- ✅ Purpose: High-Definition Television (HDTV) standard
- ✅ Color Gamut: Equivalent to sRGB
- ✅ Dynamic Range: Standard Dynamic Range (SDR)
- ✅ Brightness Range: Approximately 100 nits
👉 Suitable for:
- Traditional TV, web videos (YouTube, Vimeo)
- Projects without HDR requirements
💬 In Simple Terms: If your content is for regular monitors or TVs, this is the safest choice.
2️⃣ Rec.2020 (SDR)
- ✅ Full Name: ITU-R Recommendation BT.2020
- ✅ Purpose: Ultra High-Definition Television (UHDTV) standard
- ✅ Color Gamut: Much larger than Rec.709 (covers DCI-P3 and part of the human visual gamut)
- ✅ Dynamic Range: Still Standard Dynamic Range (SDR)
- ✅ Brightness Range: 100 nits (same as SDR)
👉 Suitable for:
- 4K, 8K video projects
- Situations where a larger color gamut is desired without needing HDR
💬 In Simple Terms: Offers richer color representation, but the dynamic range (brightness) is the same as Rec.709.
3️⃣ Rec.2100 HLG
- ✅ Full Name: ITU-R Recommendation BT.2100 Hybrid Log-Gamma
- ✅ Purpose: HDR broadcasting for television
- ✅ Color Gamut: Rec.2020
- ✅ Dynamic Range: HDR (High Dynamic Range)
- ✅ Brightness Range: Approximately 1000 nits (expandable)
👉 Suitable for:
- HDR TV broadcasts
- Scenarios requiring backward compatibility with SDR
💬 In Simple Terms: If you’re creating HDR broadcast content, HLG is the top choice as it’s compatible with non-HDR devices (no metadata needed).
4️⃣ Rec.2100 PQ
- ✅ Full Name: ITU-R Recommendation BT.2100 Perceptual Quantizer
- ✅ Purpose: HDR streaming and movies
- ✅ Color Gamut: Rec.2020
- ✅ Dynamic Range: HDR (High Dynamic Range)
- ✅ Brightness Range: Supports up to 10,000 nits (typically used at 1000-4000 nits)
👉 Suitable for:
- HDR content for streaming platforms like Netflix, Disney+
- Projects requiring precise brightness control and high brightness details
💬 In Simple Terms: The standard for cinematic and streaming HDR projects. More precise than HLG, but not backward compatible with SDR.
✅ Summary Comparison Table
| Standard | Color Gamut | Dynamic Range | Applicable Scenarios |
|---|---|---|---|
| Rec.709 SDR | Rec.709 | SDR | SD/HD videos, regular web videos |
| Rec.2020 SDR | Rec.2020 | SDR | 4K/8K projects without HDR |
| Rec.2100 HLG | Rec.2020 | HDR (HLG) | HDR broadcast television |
| Rec.2100 PQ | Rec.2020 | HDR (PQ) | HDR streaming, movies |
🎯 How to Choose?
- ➡️ For regular web videos (YouTube): Use Rec.709 SDR
- ➡️ For HDR movies/streaming: Use Rec.2100 PQ
- ➡️ For HDR TV broadcasts: Use Rec.2100 HLG
- ➡️ For 4K/8K without HDR: Use Rec.2020 SDR
Each color space not only affects the color gamut (range of colors) but also determines the color curve and brightness encoding method. Choosing the right color space in editing software is crucial to avoid issues like “color deviation” or “overexposure/underexposure”.