Visual Contrast Sensitivity Test
A calibrated screen-based test measuring contrast sensitivity at 5 spatial frequencies. Used by practitioners worldwide for biotoxin illness screening.
Before You Begin
Screen Setup
Set brightness to 50–70%. Use native resolution. No browser zoom.
Eyewear
Wear corrective glasses or contacts if you use them. No blue-light or tinted lenses.
Environment
Dim room lighting (not dark). No glare on screen. Sit comfortably at a desk.
What's Included
1
Screen Calibration~2 min
Quick PPI and gamma calibration so gratings are accurate for your screen
2
VCS Test — Both Eyes~6 min
Identify grating orientation — test stops early once your threshold is found
3
Symptom Questionnaire~7 min
51 questions across 9 domains covering all Shoemaker symptom clusters
Begin Calibration
Free · ~15 minutes total