Distance between RyngDyng and the target

The manual says that the distance between RD and the target should be 3.0 m. What is the accuracy required, or, can I have a distance of less or more?

The distance of 3.0 m refers to vertical targets such as those mounted on a wall in a training center:


As you can see in the image, the distance is measured from the front of the RD case to the front of the target.

If the target is tilt by 15° such as when mounted on a stand, then the distance is best measured from the lower front edge of the target and has got a reference value of 2.85 m. This is the same as 3 x the length of the RD case.

Now, regarding the accuracy we recommend ±5cm. You can try larger deviations and it will work if the following conditions are met:

  1. The images are still sharp. Especially when doing the chessboard calibration, both the upper and the lower chessboards need to appear sharp in the test images, not blurred.
  2. The whole target is seen by the cameras, especially if it’s a 122 cm target face. If RD is too close to the target, the observed area gets smaller.