10° Sparkle Measurement
The Effect Finish module also measures how visible and intense sparkle effects appear close to the viewing direction using a 10/0 geometry, where the surface is illuminated at 10° and observed near the normal. At this near-specular angle, sparkle contributes directly to head‑on appearance, so these parameters are important for matching what users see when looking straight at an effect coating.
Density (10°)
- Density (10°): Sparkle Density 10° is the number of visible sparkle points per 100 mm² at 10°, describing how densely the surface appears filled with sparkle elements when viewed close to the observer direction.
- Higher Density (10°) values indicate a more crowded, active sparkle field in head‑on viewing.
Area (10°)
- Area (10°): Sparkle Area 10° is the average size of detected sparkle elements at 10°, representing the typical image area covered by individual sparkles in near-specular viewing.
- Larger Area (10°) values suggest coarser, more prominent sparkle particles when viewed head‑on, while smaller values correspond to a fine, pin‑point sparkle structure.
Brightness (10°)
- Brightness (10°): Sparkle Brightness 10° is the average luminance of the sparkle points at 10°, indicating how bright each sparkle appears.
- Higher Brightness (10°) values mean that individual sparkle points are more intense.
Visibility (10°)
- Visibility (10°): Sparkle Visibility 10° is the average perceived brightness of sparkle elements at 10°, taking into account their visibility and the background colour of the material.
- This parameter is designed to correlate with human perception of how noticeable the sparkle effect is in near head‑on viewing, combining contributions from density, area and brightness against the underlying coating colour.
SpR (10°), SpG (10°), SpB (10°)
- SpR (10°): Sparkle Red 10° is the red-channel intensity of sparkle elements seen at 10°, indicating how strong the red component of the sparkle appears in near head‑on viewing.
- SpG (10°): Sparkle Green 10° is the green-channel intensity of sparkle elements seen at 10°, describing the green contribution to the sparkle impression.
- SpB (10°): Sparkle Blue 10° is the blue-channel intensity of sparkle elements seen at 10°, describing the blue component of the sparkle effect in near-specular viewing.
| Parameter group | Parameter | Unit | Description |
|---|---|---|---|
| 10° sparkle metrics | SpR (10°) | Intensity (0–255) | Red‑channel sparkle intensity at 10°, indicating how strong the red component of the sparkle appears in near head‑on viewing. |
| SpG (10°) | Intensity (0–255) | Green‑channel sparkle intensity at 10°, describing the green contribution to the sparkle impression. | |
| SpB (10°) | Intensity (0–255) | Blue‑channel sparkle intensity at 10°, describing the blue component of the sparkle effect in near-specular viewing. | |
| Density (10°) | 1/100 mm² | Number of visible sparkle points per 100 mm² at 10°, describing how densely the surface appears filled with sparkle elements. | |
| Area (10°) | mm² | Average size of detected sparkle elements at 10°, representing the typical image area covered by individual sparkles. | |
| Brightness (10°) | AU* | Average luminance of the sparkle points at 10°, indicating how bright each sparkle appears relative to the surrounding surface. | |
| Visibility (10°) | AU* | Average perceived brightness of sparkle elements at 10°, taking into account their visibility and the background colour of the material. |
*AU = arbitrary (instrument) units.