Kent:
I have been shaking my head over some of these responses and finally had to add my two cents into the mix.
It seems that many of the posters regarding this thread need to obtain, or read it if they have a copy, of "A Manual on Astronomic and Grid Azimuths by the late R. B. "Ben" Buchner, which is a very expainable text on why they should be using a reproducible bearing on all their surveys. I have never heard so many excuses from some, regarding that this is not necessary. I say B.S. If you start with a good astronomic observation from a point of survey on one of the lines or even a reference line it is possible to do many conversions from up in the real world down to that place down below. A route survey can be considered a semi-closed traverse by utilizing astronomical obsevations and taking into account the convergence of meridians between points of observation, bearings or azimuths anyway. If no monuments but one are recovered on a project and the lines are based on good astronomic observations, then you can reproduce these bearings by an astronomic observation and start out your retracement, of course this won't help you go to "whichway" from "no find".
I was going to scan the preface of Ben's book and post with this, but it is two pages long and would take up too much space. This book is one that belongs in every surveyors library.
What I can't believe is...
> >
>
> Not at all. A reproducible bearing basis doesn't require that you know the geodetic coordinates of the points connnected by the survey, merely the bearings between them. Those can be accurately determined by solar observations.
>
> :>
That's not my point Kent. (I understand the difference between bearings and coordinates.) My point is: Requiring coordinates would be inherently superior to requiring only a reproducible bearing. Why not require all surveys to put coordinates on the corners? That way you would have a reproducible bearing and a fixed point on the geoid?
I'm just curious why your not criticizing other surveyors for the practice on NOT including referenced coordinates? I hear tell there's a guy in Texas who would do it for $60 !
But, Shawn
Those monuments ARE NOT 12.005 apart. They are 12.00 apart. You accidentally set up your perfectly leveled gear about 1/32 of an inch too far to the left on one monument and about 1/32 of inch too far to the right on the other monument.
One needs to remember that the monument is the monument. A specific atom somewhere near the subjectively determined center of said monument is not the monument.
> I have never heard so many excuses from some, regarding that this is not necessary.
I would be willing to bet you lunch at the finest Mexican restaurant in Austin that virtually none of the posters who want to argue themselves blue about what a waste of time or how poor a practice surveying on some independently reproducible bearing basis like astronomic North, near-geodetic North, or grid North of a standard projection is have actually ever made a solar observation for azimuth. My own bias is to solar observations because they have given me perfectly good results and can be made during working hours in the normal course of surveying operations.
Apparently, it's time for another text or manual of instructions describing how to make solar observations. You and I both probably know that after a couple of goes, it's strictly routine work, and there are just a few tricks that markedly improve the results to get the most bang for the effort expended.
> > I have never heard so many excuses from some, regarding that this is not necessary.
>
> I would be willing to bet you lunch at the finest Mexican restaurant in Austin that virtually none of the posters who want to argue themselves blue about what a waste of time or how poor a practice surveying on some independently reproducible bearing basis like astronomic North, near-geodetic North, or grid North of a standard projection is have actually ever made a solar observation for azimuth..
As I recall, I've only worked on a few surveys that were done in True North (whatever that is). Of course, we immediately rotated them to magnetic and never looked back.
Nope never done a sun shot. Guess the boss would rather use the Promarks. Come to think of it, I've never used a buggy whip either.
> Nope never done a sun shot. Guess the boss would rather use the Promarks. Come to think of it, I've never used a buggy whip either.
Oh, so GPS does work in New Hampshire after all? Imagine that! Well, keep in mind that if you're working on a site where GPS occupations are problematic, you can probably get better azimuth solutions with sun shots if you're proficient, particularly if you're using software that can adjust several azimuth observations taken at different stations along a traverse, as Star*Net will.
What I can't believe is...
Since 2005, down here in little old Tasmania, we have been required to use grid north as survey datum and to coordinate all surveys that go to the Titles Office (essentially any survey that marks a boundary corner gets survey notes drawn up and goes there to be on the public record).
On some jobs there is a small amount of extra time required to comply, but with the majority, the ease of finding old marks makes it a time saver now having that extra information.
It is the case now that this extra information is helping everyone from government to private practice. Our surveys as a rule are quicker to do, so even the clients benefit.
It really is a win win situation.
What I can't believe is...
> Since 2005, down here in little old Tasmania, we have been required to use grid north as survey datum and to coordinate all surveys that go to the Titles Office (essentially any survey that marks a boundary corner gets survey notes drawn up and goes there to be on the public record).
I certainly won't criticize the enviable system that you are following in Tasmania, but the missing link in the US (aside from certain issues with the practitioners's skills) is the system of permanent survey marks that, as I understand it, are common reference points to survey plans in a district.
I'm probably somewhat mistaken, but it sounds as if a campaign to determine the coordinates of the permanent marks would enable sorting out the boundaries of loads of parcels tied to them. In the US those common reference monuments are mostly not present, aside from in some exceptional jurisdictions. As a result, considerably more labor is necessary to assemble all the little cadastral islands into at least archipelagos.
What I can't believe is...
> That's not my point Kent. (I understand the difference between bearings and coordinates.) My point is: Requiring coordinates would be inherently superior to requiring only a reproducible bearing. Why not require all surveys to put coordinates on the corners?
I think from what you've posted about New Hampshire surveying that expecting that level of proficiency would be a bridge too far. One step at a time and the obvious next step is to put surveys on a common, reproducible bearing basis.
Once that is done, coordinating tracts gets considerably easier.
>
> I would be willing to bet you lunch at the finest Mexican restaurant in Austin that virtually none of the posters who want to argue themselves blue about what a waste of time or how poor a practice surveying on some independently reproducible bearing basis like astronomic North, near-geodetic North, or grid North of a standard projection is have actually ever made a solar observation for azimuth. My own bias is to solar observations because they have given me perfectly good results and can be made during working hours in the normal course of surveying operations.
>
> Apparently, it's time for another text or manual of instructions describing how to make solar observations. You and I both probably know that after a couple of goes, it's strictly routine work, and there are just a few tricks that markedly improve the results to get the most bang for the effort expended.
Kent:
The next time I get in the Austin area, I'll take you up on the lunch deal. 🙂 I have a boy that lives in the Briggs vicinity. You might even be able to talk me into going out on one of your surveys with you.
> The next time I get in the Austin area, I'll take you up on the lunch deal. 🙂 I have a boy that lives in the Briggs vicinity. You might even be able to talk me into going out on one of your surveys with you.
I'll confess that you stumped me with Briggs, but it's in Burnet County near Austin, just this side of Stratton and the other side of Myers, apparently. Sure, the next time you're heading to Austin drop me a line and we'll see what can be arranged.
Briggs is about 20 miles more or less Southerly of Lampasses. I don't have an exact bearing.:-D
What I can't believe is...
I guess we are indeed lucky at the amount of coordinated government marks that are available to us. We have had some far sighted government staff in the past to set up and keep adding to and improving this network.
However even if we are out in an area we can use this facility http://www.ga.gov.au/earth-monitoring/geodesy/auspos-online-gps-processing-service.html which for a few hours of static GPS recording whilst we are off doing something else on the job will get us coordinates better than 0.05m.
Auspos supposed works world wide (and is most definitely free to use). Is there any similar things available over there?
> Well, JPH. In the above 12' strip example, I guess you'd go ahead and turn the angle off of those two axles 12.005 feet apart and run 2000' to the back corners?
Hell no.
Are you going to run a 2000' line based on nothing but a bearing that you believe that you can "reproduce"?
Hell no, at least for me.
Maybe I live in a surveying paradise where there are other things to use to determine the boundary - abutters, maybe.
I thought that we left this professional vs expert measurer debate behind.
But, Shawn
Mr Cow,
If that is even your real name. Try to keep up. I never suggested otherwise. I mention the 12.005 just to highlight how good this surveyor was. Obviously these are the monuments, but even as durable and precisely staked as the were they are useless to finding or setting those back corners. That's the point of the example.
> > If you locate two called-for monuments, you've reproduced the bearing system.
>
> Even if one of the called for monuments has been moved?
I wouldn't be basing anything on just 2 monuments, regardless of how they check. I'd need to check into at least a third, and agreement abutting owners' deeds.
I think you are letting yourself get confused on the main point. There was no other evidence of those back corners of the twelve foot strip. Had there been we would have used it. We were left with occupation. This isn't about being an expert measurer it's about expertly using measurements to reconstruct a lost boundary. And yes absolutely if I knew the bearings were astronomic I would have staked by that with no other evidence available. Wouldn't you?
No
> > > If you locate two called-for monuments, you've reproduced the bearing system.
> >
> > Even if one of the called for monuments has been moved?
>
> I wouldn't be basing anything on just 2 monuments, regardless of how they check. I'd need to check into at least a third, and agreement abutting owners' deeds.
Okay, then. You need at least three called for monuments to re-establish the bearing system. Got it.
What I can't believe is...SEB
Online Positioning User Service> USA
Seems like a very similar animal 🙂
