Lighting Ratios: Key vs. Fill Contrast

Classic portrait ratios (like 2:1, 4:1) compare the light side to the shadow side. With a single controllable key in this tool, you simulate higher or lower ratios by adjusting Fill Level, Elevation, and Azimuth.

Concept

Higher ratios (e.g., 8:1) mean stronger contrast and deeper shadows. Lower ratios (e.g., 2:1) mean gentler, flatter tones. In this tool, the “fill” is a uniform ambient/hemisphere lift—simple but great for study.

Note: This isn’t a spot-metered, multi-light ratio meter—it's a study proxy. Use it to train your eye on how Fill Level affects readability and mood.

Exercises

A) Low-Contrast (2:1 Feel)

  1. Preset: Beauty Soft or Broad Soft.
  2. Set Fill Level to 0.45–0.55.
  3. Keep Elevation fairly high and Beam Angle wide.
  4. Observe minimal shadow depth; great for “beauty” looks.
Low-contrast look with higher fill

B) Mid-Contrast (4:1 Feel)

  1. Preset: 3/4 Key (Soft).
  2. Set Fill to 0.25–0.35.
  3. Medium Beam Angle (50–60°).
  4. Study balanced shadow detail with a readable core shadow.
Moderate contrast with medium fill

C) High-Contrast (8:1+ Feel)

  1. Preset: Noir or Split Light.
  2. Set Fill to 0.00–0.10.
  3. Narrow Beam Angle (15–30°), lower Elevation.
  4. Observe strong separation and long shadows.
High-contrast look with minimal fill

Replicate with Presets

  • Beauty Soft / Broad Soft → low ratio (2:1 feel).
  • 3/4 Key (Soft) → mid ratio (≈4:1 feel).
  • Split Light / Noir → high ratio (8:1+ feel).
  • Product Front → even ratio for object studies.

Quick Tips

  • Raise Fill to reveal form; lower it to emphasize mood and silhouette.
  • Combining Softness with higher fill feels flatter and friendlier.
  • Narrow Beam Angle + low fill increases perceived contrast.