FARO Scene Version 4.5 offers you a very powerful new feature to place your scans without the need of surveyed reference points. So far you needed at least three reference points with given 3D coordinates to place a scan in space. If you did not have that information from a surveyor, you could have created your own reference points from the targets in one of your scans and use them to place the other scans around it. But in some cases, i.e. a set of scans taken from a corridor of a building, you can not see all targets from one single scan. See the link below.
Click here to download: Tips and Tricks - Cluster Registration
Keywords: cluster, faro scene