a. Root causes

  1.  If the reflection from a surface is either too strong (saturation) or too weak, then the distance cannot be calculated properly and is becoming black. The "Confidence Threshold" parameter can be used to influence this behavior.
  2.  Pixels that capture both the foreground and background deliver false distance values, namely halfway between those surfaces. They are filtered out as outliers and become black. The "Outlier Threshold" parameter can be used to influence how they are handled.
  3.  Red and noisy sections result from disruptive signals. This can be caused by interference from a second camera or strong stray light. No reflecting surfaces should be positioned in the vicinity of the camera. These will lead to stray light, which overwhelms the actual signal from weakly reflective objects.


b. Solutions

  1. Adjust the exposure time
  2.  Avoid stray light
  3.  Vary the distance and the position of the camera
  4.  Adjust the confidence threshold
  5. Adjust the outlier tolerance
  6.  Use the HDR feature