Fixing Keystone Distortion in Projection Mapping
Solve keystone distortion issues in your projections. Learn why it happens and how to correct it properly.
Keystone distortion—where projected images appear trapezoidal instead of rectangular—is a common issue in projection mapping. Here's how to fix it properly.
What Causes Keystone Distortion?
Keystone distortion occurs when a projector isn't perpendicular to the projection surface. The image appears wider at one end than the other, creating a trapezoid shape.
The Right Way to Fix It
Avoid Digital Keystone Correction: Most projectors have digital keystone correction, but this degrades image quality and resolution. It's a last resort.
Reposition the Projector: The best solution is to position the projector perpendicular to the surface. Use a mount or stand to achieve proper alignment.
Use Lens Shift: If your projector has lens shift (physical adjustment, not digital), use it to correct alignment without quality loss.
Warp in Software: Use Map Club's corner warping tools to correct distortion. This maintains image quality while fixing alignment issues.
Step-by-Step Correction
- Position the projector as perpendicular to the surface as possible
- Create a surface in Map Club matching your projection area
- Use corner handles to warp the surface until it matches the physical boundaries
- Enable X-ray mode to see the actual surface while aligning
- Fine-tune by adjusting individual corners until the image is perfectly aligned
Prevention Tips
- Plan ahead: Consider projector placement during installation planning
- Use mounts: Proper mounting hardware makes alignment easier
- Test early: Set up and align before your event or installation
- Document positions: Note projector positions for future reference
When Digital Keystone is Acceptable
If repositioning isn't possible, minimal digital keystone correction (under 10 degrees) is acceptable for temporary installations. For permanent setups, always prioritize proper positioning.
Remember: Software warping in Map Club gives you precise control without the quality loss of projector-based digital correction. Use it to achieve perfect alignment.