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No, SALSA is least squares adjustment software, you enter all your measurement observations (TS, level and Scanner prism measurements).
It performs least squares adjustment in 3 dimensions using the earths gravity geoid, you enter in standard deviations for error in each measurement, run analysis, then adjust the standard deviations (some will be over estimated and others underestimated) until the analysis passes.
I give it one known datum and a second, either a northing or easting alignment and I leave it otherwise unconstrained.
This gives very good adjustment results, that I’ve found result in perfectly aligned scans, it’s also mathematically rigorous, so you know your results are correct and you also know if there’s an issue with a piece of equipment. Eg on one occasion, I discovered the scanner had an issue with zenith angle accuracy, because zenith angle measurements with the scanner had a large error standard deviation (up to 1 degree).
Of course you can try your luck with other least squares adjustment software, I’ve just found this is what works best for me.
The text file format is simple enough, that you can write conversion scripts, or use a spreadsheet to generate the format.
Use Least Squares Analysis to QC and adjust the control observations. That should be happening on every scan project…if the control’s loose, the scans will be loose too, at least with respect to the real world.
Then georeference the scans to the control observations after registration.
The idea is to get the cloud registration and the control points as tight as possible with respect to themselves, then align the registered cloud to the control points. (That’s another least squares routine.)
“…people will come to love their oppression, to adore the technologies that undo their capacities to think.” -Neil Postman
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