Color Science

Senior Compositor

Derek Rein

https://derekvfx.ca

This seminar conducted by color scientist Peter Postma a contributor to ACES - offers an incredible overview of how light is measured and displayed digitally.

Summary

• 🎨 What is Color?: Color is the part of the electromagnetic spectrum visible to human eyes, ranging from red (long wavelengths) to purple (short wavelengths). Cameras mimic human vision by using color filters sensitive to red, green, and blue.
• 📏 Color Measurement: The XYZ color space was established in 1931, providing a method to measure and reproduce colors. It simplifies matching colors in digital systems to how they appear to the human eye.
• 🔍 Luminance and Perception: Our eyes are most sensitive to green light, which influences how we perceive brightness. This principle is crucial in video imaging and color science.
• 🖥️ Color Gamut: The range of colors a device can display or a camera can capture is limited. No three-color system can reproduce the full spectrum of human vision.
• 📉 Gamma Correction: Cameras capture light linearly, but our perception is non-linear. Gamma correction adjusts this for displays, ensuring the images look natural.
• 🖌️ Color Correction and Workflow: Modern cameras often record in raw or log formats, capturing a wide color range. Color correction is essential to adjust these images for different displays, preserving details in highlights and shadows.
• 📊 3D Look-Up Tables (LUTs): These are tools for complex color grading, allowing precise adjustments across the entire color spectrum. They are essential for professional color correction.
• 🧠 Perception vs. Reality: Our brains automatically adjust colors based on surroundings, which can affect how we perceive an image. Understanding this helps in creating accurate color corrections.
• 🖼️ ACES Workflow: The Academy Color Encoding System (ACES) is a standardized color management system that future-proofs color workflows, allowing consistent color reproduction across different devices and formats.