Okay first 2 caves are out of the way.
We are exploring and documenting an incredibility large and complex cave in Oman. There is right now, no way we can do a 3D scan of the entire cave. The scanning and meshing will take WAY to much time. However once I got my 3D skills up (and a certain amount of fitness level required of doing all the vertical stuff), I might revisit the cave and spend a few days below.
Currently we penetrated the cave moving slowing, overcoming the new obstacles for +/- 1000m long and 250m deep (I can't be specific at this point... )
Here is an image of the 3D scanner mounted on a tripod, that is mounted "hanging loaded" on an anchor point. There is 20m below me and 20m above me. The idea is to mesh the cave from below to up... if that makes any sense.
I kinda hoped it would be easier to align the point clouds automatically (I have CloudCompare running for 4 hours in an attempt to Auto Align without a result yet. It proves to that this methode is highly time consuming.
So... Steep learning curve. I have 3D experience but never worked with these large point clouds before and now still quite puzzled on how to effectively align multiple point clouds together. Initially I wanted to place an object as detection (2 tripods and then swapping scanner with the object, but since the cave is so large, I discarded the idea. If anyone had better ideas, I welcome it.
Here is a 3D scan of the bottom of a pitch.