For Texas Surveyor's-Kent
If you read the metadata, you will find that these lines are the graphic county GLO maps scanned in and shifted to SPC. It's laughable that anyone would rely on this data but unfortunately I see it frequently with our unregistered friend at Carto Remote sensing in San Antonio whose work in West Texas is always showing up on eBay. Carto garbage survey
For Texas Surveyor's-Kent
Hmm. I somehow was under the impression that the early Texas surveyors did a remarkable job on distances. Just from your posts.Maybe I've been wrong though. Rotation is a pretty easy thing to do in cad. You should try it some time.
If I draw a picture from a deed with a parcel based on it's geometry then I would surely expect some expert in the field of surveying, such as you, to be able to move this to it's correct geographic position and of course rotate it as necessary.
If the calls in the deeds are not very good, which seems very odd for Texas,then you could correct the grid to reflect that, could you not?
But forgive me. I'm just a GIS guy now I suppose.
No Deral
It's not that hard and that's what I do also and I'm not a GIS guy. I fix my base maps as I go and find corners. That way, years from now, I have an accurate picture of my O&G fields and boundaries that are relative. It also makes adjusting others for calculation purposes VERY easy.
For Texas Surveyor's-Kent
> Hmm. I somehow was under the impression that the early Texas surveyors did a remarkable job on distances. Just from your posts.Maybe I've been wrong though. Rotation is a pretty easy thing to do in cad. You should try it some time.
I've never had the idea that you read any of my posts very carefully, and this is further proof of the matter.
> If I draw a picture from a deed with a parcel based on it's geometry then I would surely expect some expert in the field of surveying, such as you, to be able to move this to it's correct geographic position and of course rotate it as necessary.
As I wrote above, clearly you don't understand the problem with retracing many 19th century land grants in Texas. They usually aren't the nice, neat geometric entities that you'd apparently like to think. The exception possibly is in the colonial grants in East Texas where many grants were run at about the same time by the same surveyor and lines were marked in timber.
The hit-and-miss patterns of settlement elsewhere in Texas outside the forests, guaranteed a generally much more complex result.
For Texas Surveyor's-Kent
It's good to know that Texas is just to complex to be mapped in a GIS.
I suppose inputing all the metes and bounds, locking a few corners into position and using least squares won't work like it does in the simple PLSS. I really don't see the difference other than the more repeatable pattern in the PLSS. Even if the design of the system in the PLSS townships is similar no two townships are exactly the same. Input of the original bearings and distances for every half mile still needs to be done to make the leasts squares work to get an iterative tune up as more solid coordinates are input. Wouldn't be that much difference anywhere, a bearing and distance is a bearing and distance.
It's going to happen sooner or later about the only question is who is going to do the work, surveyors or some other group.
For Texas Surveyor's-Kent
> It's good to know that Texas is just to complex to be mapped in a GIS.
>
> I suppose inputing all the metes and bounds, locking a few corners into position and using least squares won't work like it does in the simple PLSS.
Yes, you're right. It doesn't work. The reasons should be obvious, but apparently aren't. If any Texas surveyors are in doubt as to the facts of the matter, I'd be glad to give examples, but I've learned that it's pretty much a waste of time discussing this with folks who are mainly familiar with PLSSia.
For Texas Surveyor's-Kent
Well, as usual you didn't really answer the question. Are the GIS lines close to the deed calls distance wise? Point to point. That was the question.
And of course over the years you have made us aware of how close the early Texas surveyors got the distances compared to your findings. You have relied on these for most of your surveys it seems. You contradict yourself now it seems.
So is the GIS correct in the geometry (just the calls) or not. That was my question.
For Texas Surveyor's-Kent
I'm missing a Kuechler corner by less than 300 feet in the 80 mile res, so goin huntin it's pretty close.
For Texas Surveyor's-Kent
I never knew until today that least squares only worked in more or less cardinal directions. I suppose that is why SQUARE is in the name, eh? Wouldn't want to use the wrong tools. Is there a least non squares specific for Texas?
For Texas Surveyor's-Kent
It's the whole freaking county on one map. Most of the sections shown are about a half inch wide. The map is based on original field notes where the original surveyor reports 1900 varas square. The maps have no basis in reality and the fact that they were drawn in 1945 or whenever and then scanned in, well - geez if you can get that to work in your GIS, then TYA.
They are pretty MAPS of where the General Land Office thinks the tracts are. Until you get it tied in on the ground, it ain't a survey. But people seem to think if it's on the Railroad Commission website, it's gold.
And hey, when you buy that parcel of wasteland in West Texas, they'll ask if you want coords with that. You can punch them coords into your handheld GPS and go out and stake your corners.
>West Texas Land Sales, how can we help you?
I want a No 2 combo, twenty acres with electricity.
>You want coords with that?
Yes please. I got my magellan here in the car.
>Thank you, come again. May your improvements fall on your property.
For Texas Surveyor's-Kent
> Well, as usual you didn't really answer the question. Are the GIS lines close to the deed calls distance wise? Point to point. That was the question.
Well, since the patent calls are apt to be in significant error, particularly on distances and on bearings where the patent calls to adjoin a marked line of a senior survey, or where lines weren't actually run. What would be the value of having the map compiled exactly from the patent field notes as returned (which it isn't)? It just encourages surveyors not to do the heavy lifting that actually needs to be done to find the grant on the ground.
The Prize So Far
> The maps have no basis in reality and the fact that they were drawn in 1945 or whenever and then scanned in, well - geez if you can get that to work in your GIS, then TYA.
So far, the grand prize goes to the location of the Amasa Turner Survey in Hays County, where Wimberley is. The NE corner of the Turner Survey as shown in the GIS is in error by over 1600 ft. and the survey as plotted is rotated about 10° out of its actual position on the ground. That will be tough to beat.
For Texas Surveyor's-Kent
Well. For for years you have been telling us how well the early surveyors of Texas have done their jobs. So now you are recanting all that?
Interesting. Hmm.
For Texas Surveyor's-Kent
> Well. For for years you have been telling us how well the early surveyors of Texas have done their jobs. So now you are recanting all that?
As I said, it's clear that you haven't read many of my posts on the subject.
For Texas Surveyor's-Kent
I think you have gotten off track here, Deral. This has nothing to do with the quality of the original surveyor's work. It's about the misuse of graphic maps in a GIS system that have been scanned in and are now on the interwebs. The original surveyors did not work in the SPC system.
For Texas Surveyor's-Kent
The opportunity is for correcting the coordinates and the GIS maps.
So many surveyors just want to blow it off as a joke. The choice is either the gold mine or the shaft. To many surveyors want the shaft and wish to leave the gold mine to others. Don't suppose that society can't find someone else to fix it because they can. I should be surveyors that do the work but don't expect society to stand on their heads and beg. Legislation could flip this on a dime and give surveyors the shaft.
So the maps are not accurate. Man that's a revelation. Calling GIS a joke is not that different from calling many deeds a joke. The original PLSS notes and plats aren't pure gold either. None of these always describes reality in perfect mathematical precision. So are surveyors going to be part of the solution or more of the problem or maybe just plain irrelevant?
The money can't be found to survey it all before the GIS goes online. It will be an iterative process, self correcting slowly over time. Giant opportunity for surveyors to do the work. The public wants it and as they discover it has deficiencies maybe they will pony up the money for the corrections. Lots of work over a long time period.
For Texas Surveyor's-Kent
> The money can't be found to survey it all before the GIS goes online. It will be an iterative process, self correcting slowly over time. Giant opportunity for surveyors to do the work.
The "money can't be found", but it's a gold mine for surveyors? LOL!
For Texas Surveyor's-Kent
Ain't a surprise we disagree is it?
For Texas Surveyor's-Kent
In my wildest dreams, I never thought that this link would guide us to the old stone mound or whatever.
I merely thought is was a good tool for drafting purposes only and little hope that it was accurate.
Kent,
You would complain if you were hung with a new rope. lol!!
Randy
For Texas Surveyor's-Kent
> In my wildest dreams, I never thought that this link would guide us to the old stone mound or whatever.
>
> I merely thought is was a good tool for drafting purposes only and little hope that it was accurate.
>
> Kent,
>
> You would complain if you were hung with a new rope. lol!!
Randy, the problem is that there are surveyors out there who are always looking for the "easy" button and wouldn't hesitate to import that POS GIS representation of the original land grant lines as if they meant something. Naturally, they pretty much don't.
I think it's remarkably well settled that the original surveys are to be located following the footsteps of the original locating surveyor and if there is a different location shown on the GLO county map (upon which the POS GIS was based), well, that location doesn't control.
The GIS is not a bad tool as long as the surveyor keeps in mind that the locations may be in error by as much as 1600 ft. And with that much error as a real prospect (based upon my sample of corners above), what really can you do with the GIS data? Knowing that the GIS data is grossly defective, it's not as if you can ethically put it on a map as qualify it with a note saying "Original patent lines per Texas Railroad Commission Grabass GIS" or something like that.
