Angle of incidence... The stated range is a max range under the optimum conditions of a vertical white reflective surface that is perpendicular to the scanner. Due to the fact that the world is very dynamic the effective range often ends up being much less. The problem on some horizontal surfaces(like the ground far from the scanner or curved surfaces) is that the laser hits the surface at a very sharp angle which elongates and distorts the beam from a spot or circle to an elongated spot, then even a line. At some point this distortion either provides insufficient reflected light back to the scanner or the scanner throws out this non-viable point due to the confusion.
Here are some simple images that may help:
Notice how the spot becomes longer as the angle to the target is decreased. To the best of my limited understanding, this "angle of incidence" is the primary reason why the range is not the same for all surfaces. Maybe someone that knows more will elaborate or correct me.
BTW, Welcome to the Forum Philip
Outdoor Scan Settings and Procedure
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Re: Outdoor Scan Settings and Procedure
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Re: Outdoor Scan Settings and Procedure
Layperson terms:philip.feghaly wrote:Hello guys, I'm new to this forum and to scanning,
may i ask why the faro's x130 range is 130 m but you can only get far, 15 to 20 meters between scans for a good result ?
can someone plz explain the need for the extra 110 m or 310 m ??
im a bit lost !
If your talking about registration with spheres, its because the size of the sphere will determine how far away that you can be for the software to "see it" as a viable registration tool (as mentioned before, you need so many points on the sphere to make it work). The smaller the sphere, the closer you need to be. You may still be able to pick up points on a vertical surface 130 m away, but you wouldn't be able to use it as a registration tool (plane) because it doesn't have enough points to give the software and average to formulate a surface and its very possible that the actual distance may be incorrect. In regards to getting the 330 (assuming you mean why buy the farther machine) is it should give you the ability to shoot farther and get that vertical surface that is 130 away and get enough points to use it as a "plane" if needed, or at least be confident that you can use the points at that distance and they should be accurate.