Complete Guide to Video Scopes: Histogram, Vectorscope, Waveform
Video scopes are essential tools for professional video production, color grading, and exposure analysis. Unlike your eyes, which can be fooled by ambient lighting and screen calibration, scopes provide objective technical data about your video signal. This guide covers how to use the video scopes available in DualView for comparison and analysis.
What Are Video Scopes?
Video scopes are visual representations of the technical properties of your image. They show information about brightness levels, color distribution, and saturation that isn't visible when just looking at the picture. Broadcast facilities have used scopes for decades to ensure signals meet technical specifications.
Modern digital workflows use the same concepts:
- Histogram — Distribution of brightness values
- Vectorscope (Color Wheel) — Hue and saturation information
- Waveform Monitor — Luminance values across the frame
- False Color — Exposure as a color overlay
- Focus Peaking — Sharp edge highlighting
Understanding the Histogram
The histogram shows how brightness values are distributed across your image. The left side represents shadows (dark pixels), the middle represents midtones, and the right represents highlights (bright pixels). The height at any point shows how many pixels have that brightness value.
Reading the Histogram
| Pattern | Meaning | Action |
|---|---|---|
| Spike on left edge | Crushed blacks (clipping) | Raise shadows or add fill light |
| Spike on right edge | Blown highlights (clipping) | Reduce exposure or pull highlights |
| Data spread across range | Well-exposed image | No changes needed |
| Gap on right side | Underexposed | Increase exposure |
DualView shows separate RGB channels in the histogram. If one channel is clipping while others aren't, you have a color channel that's out of gamut. This often happens with highly saturated colors like neon signs or sunsets.
The Color Wheel (Vectorscope)
The vectorscope, displayed as a color wheel in DualView, shows the chrominance (color) information in your image. The angle from center indicates the hue (which color), and the distance from center indicates saturation (how intense the color is).
Key Uses
- White balance check — A neutral image should cluster near the center
- Skin tone line — Skin tones of all ethnicities fall along a specific line
- Color matching — Match the vectorscope patterns between shots for consistency
- Saturation check — Data extending to the edge indicates highly saturated colors
False Color for Exposure
False color replaces the actual colors in your image with a rainbow gradient based on brightness levels. Each color represents a specific exposure zone, making it easy to identify problem areas at a glance.
| Color | IRE Range | What It Means |
|---|---|---|
| Purple/Blue | 0-20 IRE | Underexposed, crushed shadows |
| Cyan/Green | 20-40 IRE | Proper shadow detail |
| Green/Yellow | 40-60 IRE | Mid-gray, proper exposure |
| Yellow | 55-65 IRE | Skin tone target zone |
| Orange/Red | 70-90 IRE | Highlights approaching clipping |
| Pink/White | 90-100 IRE | Clipped highlights |
Focus Peaking
Focus peaking highlights the sharpest edges in your image with a colored overlay. This helps you verify focus accuracy and compare sharpness between two shots. In DualView, you can enable focus peaking on both sides of a comparison to see which shot is sharper.
Use Cases
- Comparing autofocus accuracy between cameras
- Evaluating lens sharpness at different apertures
- Checking AI upscaler edge preservation
- Verifying sharpening settings in post
Keyboard Shortcuts
DualView provides quick keyboard access to all video scopes:
| Key | Function |
|---|---|
| W | Toggle video scopes panel |
| P | Toggle focus peaking overlay |
| Z | Toggle zebra stripes |
Using Scopes for A/B Comparison
The real power of DualView is using scopes to compare two images or videos objectively. Here's how to use scopes for common comparison tasks:
Comparing Color Grades
- Load original and graded versions
- Press W to show video scopes
- Compare the vectorscope patterns to see how color shifted
- Compare histograms to see contrast/exposure changes
Comparing Compression Quality
- Load original and compressed versions
- Enable focus peaking with P
- Look for reduced edge definition in the compressed version
- Check histogram for reduced tonal range (banding)
Conclusion
Video scopes are invaluable tools for objective image analysis. Whether you're color grading, comparing compression, or evaluating focus, scopes give you technical data that your eyes alone can't provide. DualView's integrated scopes make it easy to use these professional tools for any comparison workflow.