Scope64

A lightweight real-time LAB vectorscope for photography and video color grading.

Website: https://scope64.io

GitHub: https://github.com/Scope64/LAB-Vectorscope

Last Update: 2026-02-10

What is it?

Scope64 is a minimalist tool that displays a real-time LAB color vectorscope of any screen region. Perfect for:

• White Balance → Neutral grays should be centered (a=0, b=0)
• Skin Tones → All skin tones align on the 45° line, regardless of ethnicity
• Color Cast Detection → Instantly see Magenta/Green or Yellow/Blue shifts

Why LAB?

The LAB color space separates luminosity from chrominance, making it ideal for color correction. The "skin tone line" at 45° is universal and works for all skin colors.

Features

• Real-time vectorscope (10 FPS)
• Skin tone reference line (45°)
• Dynamic range display (L* and EV)
• Color temperature estimation (Kelvin)
• Clipping indicators (shadows/highlights)
• Dominant color detection
• Screenshot export (PNG)
• Always on top
• Cross-platform (Windows, macOS, Linux)
• Ultra lightweight (~11 KB)

Requirements

• Java 8 or higher
• Download and install JAVA JDK from: https://www.oracle.com/java/technologies/downloads/

Usage

java -jar Scope64.jar

1. Click on the window to start selection
2. Draw a rectangle on any screen area
3. The vectorscope updates in real-time
4. Click again to select a new area

Keyboard Shortcuts

Key	Action
S	Save screenshot to Desktop
ESC	Quit
Left Click	New selection

Display Info

Position	Information
Top left	Shadow clipping % Lstar < 3
Top right	Highlight clipping % Lstar > 97
Left	Dynamic range (D), EV stops, Color temp (K)
Right	Dominant color cast

How to Read the Vectorscope

• Center = Neutral (no color cast)
• Top = Magenta
• Bottom = Green
• Right = Yellow
• Left = Blue
• 45° line = Skin tone reference

Use Cases

White Balance

Select a gray/neutral area. If the points are not centered, your white balance needs adjustment.

Skin Tones

Select a skin area. Points should align along the 45° line. If they drift toward green or magenta, adjust your tint.

Color Cast Detection

Select the entire image. The dominant color indicator shows which direction your image is shifted.

License

MIT License - Free to use, modify, and distribute.

Author

Copyright (c) 1996-2026 - Olivier FABRE

Thanks to Claude AI / Anthropic for algorithms optimization.

Made with passion for photographers and colorists who understand the power of LAB.