Clearly, Kris
> Seeing the BIG PICTURE is one thing that SPC really helps and you end up with enough data to satisfy that old addage I was told years ago
>
> "The difference in a bad decision and a mediocre decision is data. There are no good decisions".
>
> Then it followed with
> "You don't have to be a good surveyor if you find all the corners."
> SPC have allowed me to do both with better and faster results.
Obviously, Kris, you have the disadvantage of actually being engaged in Texas surveying. The huge advantage of being able to assemble the big picture is what the SPCS is all about. In parts of West Texas, that big picture extends for literally hundreds of miles.
Some State Plane History
The magic CCF, Nothing like the fun of scaling, then unscaling, do I multiply or divide. So simple Kent can do it!
So what's the magic to get the bearing inline with North. The CARF (combined angular rotation factor)? Is it right, left, up or down. Maybe who gives a crap the original bearing doesn't matter anyway.
Oh yeah, let's not do anything for engineers, geezz one of them invented the wheel and screwed everything up.
You're one strange dude!
Some State Plane History
> So what's the magic to get the bearing inline with North. The CARF (combined angular rotation factor)? Is it right, left, up or down. Maybe who gives a crap the original bearing doesn't matter anyway.
Usually, when you're dealing with an actual survey that you're retracing (novel concept in Utah, I know) the absolute direction of the record bearing doesn't matter that much. There will be an average index error in azimuths to be determined (novel concept in Utah, I know), unless you are an ... engineer (in Utah). In that case, all bets are off. LOL!
Some State Plane History
An expert in PLSS retracement such as yourself knows that they oriented the whole thing to North (not SPC Grid North that hadn't been invented by an engineer yet).
I used SPC's for a few years and then dropped them because of the hassle of always needing the rotate and scale the work to match the actual. It was just easier to find stuff North than some cockeyed rotated angle from grid north. If I do need SPC's its just a few clicks away, all my work since 1999 is tied in to NAD83.
You can poke all the fun at engineers you like (popular with some surveyors) but I did the time and completed the education instead of dropping out. Then I did more education to meet the requirements for surveyor.
You may LOL all you want, but on this issue of using LDP's to enhance surveying and engineering you are making yourself the laughing stock much as you have tried to pin stuff on others. SPC's work and can be accurate but there are better ways that are coming on line. None of the record, bearings and distances, was originally done in SPC's before the 1930's and little since.
As others have tried to point out, if you use GPS your basic coordinates are ECEF (whether you realize it or not). It's all just some computer computations from there. A SPC is just a projection, a high distortion projection using the same math as a low distortion projection.
Your toolbox is truly lacking, maybe you're just cheap when it comes to tools or can't understand how to operate them so no need to buy them. I wouldn't buy a monkey wrench if I couldn't figure out how to make it work!
Some State Plane History
> You may LOL all you want, but on this issue of using LDP's to enhance surveying and engineering you are making yourself the laughing stock much as you have tried to pin stuff on others. [...] None of the record, bearings and distances, was originally done in SPC's before the 1930's and little since.
So, there just isn't any way that a surveyor like you can retrace a survey run before 1930 using the SPCS? LOL. I get the idea that you really don't know how foolish that sounds.
Some State Plane History
".....you really don't know how foolish that sounds."
THAT sounds just like like another poster that we all know and love.
LOL
Don
Some State Plane History>
I don't think that Kent has ever claimed to be: "An expert in PLSS re-tracement such as yourself....."
A Texas surveyor for sure, but never a PLSS surveyor...at least not that I am aware of... Also, listening to him argue about geodetic survey is an amusement, not an education. I prefer someone like Loyal when it come to understanding State plane Coords...
As for your time frame of SPC prior to 1930 can't be reproduced, I'd have to disagree. Here in MA I've used them from the 1800's to good effect...
Some State Plane History>
> A Texas surveyor for sure, but never a PLSS surveyor...at least not that I am aware of... Also, listening to him argue about geodetic survey is an amusement, not an education.
Yes, any surveyor who is expecting to learn how to survey by reading an internet message board is in worse shape than a certain Utah poster who thinks that retracing old surveys run before 1930 in the SPCS is just impossible. About all one can do is laugh at the cluelessness. Having used the SPCS for about 25 years and for virtually all surveys for fifteen or sixteen, I know how ridiculous the claims being thrown around are. You can either LOL at the idiocy or find it depressing.
Some State Plane History
I certainly don't have any problem with folks using State Plane Coordinates for any purpose that blows their skirt up. I personally don't think that it is a good system for Cadastral work here in the Great Basin, BUT if that's all you know how to do, then go for it.
The problem is simply that NOT many folks appear to KNOW HOW TO DO IT, so we get a plethora of locally or globally MODIFIED pseudo SPCs with little or no supporting metadata. In essence, everything is still “locally controlled” just as it was in the 19th Century, so when the MONUMENTS are gone, they are gone forever, the [local] Coordinate NUMBERS are just BIGGER!
I suppose that it really just comes down to METADATA. If scaling and rotating EVERY plat, description, Patent, and survey into an SPC paradigm BEFORE even visiting the field is your modus operandi of choice, then fine. But if that's how you want to play, then at least play by the rules, and leave it all “on the grid” and clearly state the origin and methodology used to create those BIG NUMBERS. If you want (or need) to scale the distances up to the real world, then by all means do so (BUT NOT the Coordinates).
Personally...I think that it is crazy to use SPC Grid Bearings here in the Western US. The entire cadastral fabric is based on True [astronomic] Bearings, and rotating things up to (and often in excess of) 1 degree is just plain silly. GRANTED...ANY projection (LDP or otherwise) is going to impart some rotation somewhere. Even 1 arc-minute is certainly non-trivial, but it beats the crap out of 1 degree. Three arc-seconds equals a centimeter in a half a mile, so where do you draw the line?
The MONUMENTS are still going to CONTROL (assuming that they are extant), so it really boils down to getting GOOD (reproducible) geodetic positions on the current CORNERS/MONUMENTS. State Plane Coordinates (REAL ones), UTM, LLH, XYZ, and LDP will all do that (ASSUMING of course that these values were PROPERLY constrained, computed, and supported by reasonable METADATA).
Loyal
Loyal
I have never used SPCs so I do not understand all the arguments here, but for me; I will take your arguments over the expert measurer who would never bend a line through subsequent valid junior monuments!
That is what is silly!
Keith
Some State Plane History
Actually I've done quite a bit of PLSS retracement using SPC's. It's a pain in the butt to scale and rotate and unscale and unrotate and always be calculating the distance and angle to where you are or should be looking from what your computer is reading out. This can all be overcome simply by using a projection that more closely matches what the PLSS surveyors where told to do. Why make it so hard and complicated? The PLSS was intended to be on astronomic bearings and ground distances, so why not stick close to that?
If you want to belittle those that don't standardize everything to the way you do it you can online but there are other ways to do the math that work more efficient for those not welded into their own box.
Some State Plane History
Leon nailed it...
The “argument” that THIS (or THAT) WAY to do things, is the ONLY RIGHT WAY, simply because that's how “I do it,” or that's the way “we do it in Xxxxxx” is just that, an argument!
What we really should be discussing, is HOW “best” to align and constrain our “coordinates” to the NSRS, and THEN how “best” to express our findings (coordinates and linear relationships) on Plats, Records of Survey, and YES...descriptions.
A tabulated list of [REAL] State Plane Coordinates WITH Elevations OR Ellipsoid Heights, would certainly fill the bill. A tabulated list of Latitude, Longitude, Ellipsoid Heights, or Geocentric XYZ, would also. But that only addresses HALF of the “problem.”
When I see a GLO/BLM Plat that says “North 80 chains,” I know EXACTLY what that MEANS (basis of bearing, linear paradigm, BINGO). It doesn't really matter whether the plat is dated 1856 or 2011!
When I see a “modern” ALTA, ROS, or description that has bearings to the nearest arc-second, and distances to the nearest thousandth of a foot, BUT only a cryptic (and ONLY locally reproducible) Basis of Bearing, and NO MENTION whatsoever about what the distances relate to (elevation/height in particular), then it becomes a guessing game.
Loyal
Some State Plane History
I ran Cadastral resurveys using latitude and departures for about 15 years.
Take a solar in the morning and one at the end of the day.
Find a corner to start from and off you go.
We also use GPS and State Plane Coordinates when it fits our needs.
DJJ
Some State Plane History
> Actually I've done quite a bit of PLSS retracement using SPC's. It's a pain in the butt to scale and rotate and unscale and unrotate and always be calculating the distance and angle to where you are or should be looking from what your computer is reading out. This can all be overcome simply by using a projection that more closely matches what the PLSS surveyors where told to do.
So, uh, what projection might you have in mind in which all projection bearings are true? Like, none? It's exceptionally dishonest to claim that the non-equality of grid and true is an issue that disappears. All you're doing is reducing the mapping angle, which is an unimpressive accomplishment.
Some State Plane History
Well Kent, I would try and explain what:
"using a projection that more closely matches what the PLSS..."
Means, but I'm afraid that [in your case] it would be a waste of time and band width.
Loyal
Some State Plane History
Loyal, you said> "When I see a “modern” ALTA, ROS, or description that has bearings to the nearest arc-second, and distances to the nearest thousandth of a foot, BUT only a cryptic (and ONLY locally reproducible) Basis of Bearing, and NO MENTION whatsoever about what the distances relate to (elevation/height in particular), then it becomes a guessing game."
I am so used to this method of surveying that it's difficult for me to get around to using SPC for projects, unless required. For the most part the basis of bearing couldn't be less important since there are monuments shown that I can tie into.
We are required to list our basis of bearings but 99% of the time (if not more) it's just a reference to a plan book and page, or land court case. We're measuring angles and distances for local use, only, local coord basis, local basis of bearing (probably carried forward from an ancient mag bearing the in 1800's)
this is just the difference in types of survey that we do. I've done solar shots to determine a basis of bearing when i worked in TN, but only maybe 5 times...
If you see one of my plats you will know that I'm a "flatlander" in an area where 130' MSL is hard to find, my distances are horizontal and my north arrow will tell you where my basis of bearings came from. My bet is that you could reproduce it pretty accurately without SPC...
Some State Plane History
>I am so used to this method of surveying that it's difficult for me to get around to using SPC for projects, unless required.
I have a hard time imagining running my survey company without using SPC. Since I started using GPS (around 1996) I have gathered SPC coordinates on hundreds of property corners, abstract lines, and other features of interest in my work area. Being able to see all those points relative to one another and relative to new projects is a very valuable tool to me.
Some State Plane History
Foggy:
I hear ya, and in MANY cases (and areas) that's just dandy! But when we start talking about a NEW ALTA covering a couple square miles or so with two-three thousand feet of relief, that just doesn't cut it! ESPECIALLY when the fence builders bulldozed ALL of the fricking lines.
Robert,
I hear you TOO! But the KEY is georeferenced coordinates (SPC/H, UTM/H, LDP/H, LLH, XYZ). If you have any (or all) of those, then you are walking in tall cotton. In fact...if you have any one, you can EASILY generate ALL of the others (in about a microsecond).
Loyal
1. A friend pointed me to this discussion. I am grateful.
2. Although I am a novice at posting replies, I have read and accept the terms of use for the forum. If I venture into the gray area or cross the boundary of appropriateness, I'll be happy to back-off.
3. I counted 18 different persons posting under this thread - many that I recognize, admire, and respect. Any item/issue of disagreement is not intended to be disrespectful. I will gladly listen and learn from other thoughtful viewpoints.
4. It appears there is some mis-information and misunderstanding on the use of both state plane coordinates and earth-centered earth-fixed (ECEF) coordinates.
5. I have devoted a career to teaching, among other things, use of coordinate systems and have posted information at http://www.globalcogo.com . See in particular the link to article and papers.
6. Although state plane coordinates are very useful in come cases, the fact remains that map projections (state plane coordinates) are a two-dimensional model and we work with three-dimensional data. That makes state plane coordinates obsolete.
7. But, it is prudent to provide a better way to do something before removing a useful tool. That better way is the global spatial data model (GSDM) based upon the ECEF system native to the GNSS (or GPS) system.
8. Reasons for using the GSDM include:
a. There is one set of equations world-wide. They really are not that complex.
b. Full geometrial integrity is preserved by the GSDM.
c. The local tangent plane distance is readily computed.
d. The direction from here to there is the true geodetic azimuth with respect to the meridian through the standpoint.
e. The GSDM accommodates input of standard deviations of any/all quantities. With those values in the data base, the standard deviation of any inverse direction and/or distance is readily available.
f. Many others
9. I'll be happy to respond to inquiries/questions.
a.
Sorry about that. I thought I was posting a small postage stamp photo that appears to the right of the header. I'll try to get it right the next time.
