Do you need to use Least Squares to meet the "Relative positional Precision" or is using the old Compass method acceptable?
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The Hack
Most definately modern TS with tight angles and distances all around, including traverse and sideshot with a closed loop, balance angles and if good results use a crandal routine for closure..
That of course would depend upon the acerage of the property and if you have the opportunity to make diagonal closures thru the middle of the outer boundary and least squares would definately improve.
On any less than desireable results on a traverse loop over 20ac you may want to use compass routine after double checking any possible bad setups.
After a tight closure after balancing the angles, never can go wrong with crandal.
It's funny, just as I started to do ALTAs starnet came out so I?ÿbegan using it for?ÿtraversing adjustments and my reports to make it easier to show that I met the standard, it became clear that it wasn't any different than compass rule until you made cross ties and changed the weighting.?ÿ I don't do many ALTAs nor have I had any Relative positional police ever ask for a report, but if you are doing an ALTA I would recommend least squares. No doubt you could dazzle?ÿmost by showing them your compass rule calculations, but?ÿtoday least square programs are so much faster it seems, but then I usually did compass rule in the book by hand.?ÿ
With GPS programs you can generate all kinds of reports to "prove" that you met the standards, many ways to do it that I've seen.
Lots of people do ALTAs without LS. So I guess that you can. I just can't figure why you would want to.?ÿ?ÿ
If you don't want to learn how you could probably find someone here to run your data for a small fee.
I started composing a post about the dismal technical standards behind most ALTAs -- the ones churned out by the dozens by ALTA mills supporting corporate acquisitions -- but I decided it was better not to stray from the original question, and save myself some heartburn in the at the same time.
It looks to me like the "Minimum Standard Detail Requirements for ALTA/NSPS Land Title Surveys (Effective February 23, 2016)" clearly require least squares for determining relative positional precision. Paragraph 3E(i) says:
??Relative Positional Precision? means the length of the semi-major axis, expressed in feet or meters, of the error ellipse representing the uncertainty due to random errors in measurements in the location of the monument, or witness, marking any corner of the surveyed property relative to the monument, or witness, marking any other corner of the surveyed property at the 95 percent confidence level. ?ÿRelative Positional Precision is estimated by the results of a correctly weighted least squares adjustment of the survey.
2016 Minimum Standard Detail Requirements for ALTA/NSPS Land ...
