Rec.2020 vs Rec.2100
While Rec.709 has been the standard for HD television for decades, Rec.2020 and Rec.2100 are the modern standards designed for the era of 4K, 8K, and HDR (High Dynamic Range).
Think of them as the "Next Generation" blueprints for how color and light are handled.
1. Rec.2020 (The "UHD" Standard)
Released in 2012, BT.2020 is the standard for Ultra High Definition (UHD) television. It defines a massive increase in the variety of colors a screen can show.
- Color Gamut (Width): This is the biggest feature. Rec.2020 covers about 75% of the colors the human eye can see, whereas Rec.709 (HD) only covers about 35%.
- Bit Depth: It requires a minimum of 10-bit or 12-bit. You cannot have a 100% "legal" Rec.2020 image in 8-bit.
- Resolution: It is strictly for 4K (3840x2160) and 8K (7680x4320).
- SDR Focus: While it is a "wide" space, it was originally designed for Standard Dynamic Range (SDR). It tells you how many colors you have, but not necessarily how bright the screen can get.
2. Rec.2100 (The "HDR" Standard)
Released in 2016, BT.2100 is an extension of Rec.2020 specifically designed for HDR.
- Gamut: It uses the same massive color "bucket" as Rec.2020.
- Dynamic Range (Height): This is the key difference. Rec.2100 adds the rules for how the brightness (luminance) should behave. It moves away from the old "Gamma" system and introduces two new ways to handle light:
- PQ (Perceptual Quantizer / ST.2084): Used for HDR10, HDR10+, and Dolby Vision. It can handle brightness up to 10,000 nits.
- HLG (Hybrid Log-Gamma): Designed for Live Broadcast (BBC/NHK). It is "backwards compatible," meaning it can play on an SDR TV and still look okay, while looking like HDR on an HDR TV.
Key Differences at a Glance
| Feature | Rec.709 | Rec.2020 | Rec.2100 |
|---|---|---|---|
| Typical Use | HD TV / Standard Web | 4K UHD Mastering | HDR (Cinema & YouTube) |
| Color Range | Narrow (SDR) | Wide (WCG) | Wide (WCG) |
| Brightness | Standard (up to ~100 nits) | Standard (SDR) | High (up to 10,000 nits) |
| Bit Depth | 8-bit or 10-bit | 10-bit or 12-bit | 10-bit or 12-bit |
| Gamma/EOTF | Power Function (2.4) | Power Function (2.4) | PQ or HLG |
When should you use them in DaVinci Resolve?
Use Rec.2020 if:
- You are delivering a 4K SDR video and want to ensure the widest color compatibility for future screens.
- You are working in a "Wide Gamut" pipeline (like DaVinci Wide Gamut) and need a standard "container" to export your high-quality color work without it being HDR.
Use Rec.2100 if:
- You are delivering HDR content for YouTube HDR, Netflix, or Disney+.
- Warning: Do not export in Rec.2100 unless you have an HDR-certified monitor (like a Pro Display XDR, a high-end OLED, or a specialized Flanders Scientific monitor). If you grade HDR on a standard SDR screen, the colors will look completely wrong (either washed out or extremely "neon") when viewed by others.
The "Codec" Connection
To successfully export Rec.2100 (HDR), you must use the settings we discussed earlier:
- Codec: H.265 or ProRes 422 HQ / 4444.
- Profile: Main 10 (10-bit is mandatory for HDR).
- Chroma: 4:2:0 is fine for delivery, but 4:2:2 is better for mastering.
Pro Tip for YouTube HDR: If you want to upload HDR to YouTube, set your DaVinci Resolve Output Color Space to Rec.2100 ST2084. When you upload the file, YouTube will see the "Metadata" inside the file and automatically trigger the "HDR" badge on the video player.
Is Rec.2020 the same as Rec.2100 in terms of Input Color Space?
Yes, for the "Input Color Space" dropdown, Rec.2020 and Rec.2100 they are exactly the same.
Rec.2100 = Rec.2020 Color Space + HDR Gamma (PQ or HLG)