The process of photographing a location's complete lighting environment using multiple exposures and specialized equipment – creates High Dynamic Range Images used for accurate CG lighting, reflections, and integration of digital elements into live-action footage.
What is HDRI Capture?
HDRI Capture is the process of recording a complete lighting environment for VFX purposes. Through bracketed exposures and 360° photography, all light sources, reflections, and colors are captured, which are later used for CG lighting and reflections.
Purpose
| Application | Description |
|---|---|
| CG Lighting | Environment lighting for 3D |
| Reflections | Realistic reflections |
| Color Reference | Color temperature |
| IBL | Image Based Lighting |
Equipment
| Equipment | Function |
|---|---|
| DSLR/Mirrorless | Capture camera |
| Fisheye Lens | 180°+ capture |
| Tripod | Stable stand |
| Nodal Mount | Parallax-free |
360° Capture
| Method | Description |
|---|---|
| Fisheye | 2-3 shots |
| Rectilinear | Multiple shots |
| Panorama Head | Precise rotation |
| Spherical Camera | Automatic |
Bracketed Exposures
| Exposure | Captured |
|---|---|
| Underexposed | Highlights |
| Normal | Midtones |
| Overexposed | Shadows |
| Range | ±5-9 Stops |
Typical Workflow
| Step | Description |
|---|---|
| Position | Within the scene |
| Align | Horizon level |
| Bracketing | Exposure series |
| Rotate | All directions |
Capture Positions
| Position | Reason |
|---|---|
| Where CG will be | Exact lighting |
| Eye level | Perspective |
| Multiple points | For large scenes |
| Before light changes | For each setup |
Chrome Ball Method
| Aspect | Description |
|---|---|
| Photograph ball | Capture reflection |
| Bracketed exposures | HDR range |
| Simpler | Less equipment |
| Limitation | Not full 360° |
Dedicated 360° Camera
| Advantage | Description |
|---|---|
| Fast | One click |
| Automatic | Stitching internal |
| Compact | Little equipment |
| Disadvantage | Often less range |
Software for Stitching
| Tool | Description |
|---|---|
| PTGui | Industry standard |
| Hugin | Open Source |
| Photoshop | Photomerge |
| Pano2VR | Specialized |
HDR Merge
| Software | Function |
|---|---|
| Photomatix | HDR Merge |
| Luminance HDR | Open Source |
| Photoshop | Merge to HDR |
| Affinity | HDR support |
Output Formats
| Format | Properties |
|---|---|
| EXR | Industry standard |
| HDR | Radiance Format |
| TIFF 32-bit | Alternative |
| Lat-Long | Mapping type |
Quality Factors
| Factor | Meaning |
|---|---|
| Dynamic Range | Sufficient brackets |
| Resolution | For reflections |
| Stitching | Seamless |
| No Ghosting | Static scene |
Challenges
| Problem | Solution |
|---|---|
| Movement | Work quickly |
| Crew in frame | Mask out |
| Changing Light | Fast capture |
| Equipment shadows | Retouching |
Post-Processing
| Step | Description |
|---|---|
| Stitching | Assembly |
| HDR Merge | Combine exposures |
| Clean-Up | Remove tripod |
| Tonemapping | For preview |
Cleanup
| Element | Method |
|---|---|
| Tripod | Clone/Heal |
| Photographer | Remove from image |
| Crew | Retouching |
| Equipment | Mask out |
Usage in CG
| Application | Software |
|---|---|
| Maya | IBL Dome |
| Houdini | Environment Light |
| Blender | World Shader |
| Nuke | Reflection/Lighting |
IBL Setup
| Step | Description |
|---|---|
| Load HDRI | As environment |
| Rotation | Align correctly |
| Intensity | Adjust |
| Ground Plane | Shadow catcher |
On-Set Protocol
| Step | Description |
|---|---|
| Timing | At light setup |
| Mark position | For repetition |
| Document shot | Assignment |
| Backup | Secure immediately |
Cost-Benefit
| Aspect | Factor |
|---|---|
| Time investment | 5-15 min/setup |
| Equipment | One-time investment |
| Post-production savings | Significant |
| Quality upgrade | Visible |
Best Practices
| Practice | Reason |
|---|---|
| Before each setup | When lighting changes |
| High resolution | For detail |
| Wide range | Capture all lights |
| Document | Shot assignment |
Today
HDRI Capture is indispensable for professional VFX production. The combination of bracketed exposures, 360° photography, and specialized software enables CG lighting that perfectly matches the filmed environment. The time invested on set saves many times over in post-production.