Ngs Faq Draft

[caseyb]

Welcome to the National Geodetic Survey’s (NGS) Frequently Asked Question (FAQ) thread.

There are a lot of question that routinely come up by people new to the idea of submitting recoveries to NGS. Before you make a new post in this forum, please take a minute to read through this thread. Your question may have already been answered.

 

Q: What is the National Geodetic Survey (NGS) and why does it have a separate forum?

 

A: NGS is a federal government agency within the National Oceanic Atmospheric Administration or NOAA. NGS is responsible for maintaining the National Spatial Reference System (NSRS) which is the basis for all mapping and surveying in the USA.

When geocachers search for “benchmarks” they are in fact searching for the objects that make up the NSRS. When you submit a “find” to geocaching.com, NGS does not receive the information. The information about the status and, in some cases the position (more info below), of these benchmarks can potentially be of value to the NSRS. By submitting a separate report to NGS, you can help maintain the NSRS and provide valuable information to future users. This forum was created by the founder of Geocaching.com to help assist in the maintenance of the NSRS.

 

Q: Do I have to log my finds with NGS?

 

A: No. Submitting a report to NGS is 100% optional. If you are just benchmark hunting for fun, and are not interested in submitting your data to the government that is fine. Have fun.

 

Q: Why should I log my finds with NGS?

 

A: Again, whether or not to log a find with NGS is up to you. You are never obligated to do so. However, in certain cases the information you find when looking for a benchmark may be valuable. For example, if you find a mark that has not been recovered in a long time or a mark that has been destroyed, that is valuable. If you find an error in the datasheet, or if you discover that something has changed in the description of how to find the mark, you have information that may be of high value to someone. By reporting it to NGS you are performing a valuable public service by sharing that important information with people who need it.

 

Q: Where do I submit reports to NGS?

 

A: NGS has an on-line mark recovery page. To submit a report, just visit http://www.ngs.noaa.gov/FORMS_PROCESSING-c...y_entry_www.prl

 

Q: I am not a professional surveyor. Am I qualified to be submitting a recovery report to NGS?

 

A: Yes. You do not need to be a surveyor to provide useful information. However, there definitely are a few things you should be aware of. Make sure the data you are submitting is accurate! If you are new to the game, you might want to hold off before sending in any reports of “not found”. You should know the difference between a reference mark and a triangulation station before submitting something dealing with that. There are lots of people in these forums who are happy to answer any questions you may have.

 

Q: What is the official, exactly, legal, 100% accurate definitions of “good”, “poor”, “not found” and “destroyed”?

 

A: There are no official definitions. I am sorry, but you will have to actually use your own judgment here. Destroyed marks are handled separately and should not be submitted through the mark recovery page. Destroyed marks are handled by emailing Deb.brown@noaa.gov

 

Here are some guidelines used by NGS employees to describe the condition of a mark:

 

GOOD -- Recovered as described on the datasheet; looks healthy and happy.

 

POOR -- Recovered, but shows some alarming evidence of damage or movement. Often the marks can get run over, or frost heaved, or the ground is just too soft to support it. If the mark is scarred and leaning, thrust up from the ground like a mushroom and/or surrounded by tractor ruts, it's poor. If the disk is gone but some evidence (stem) remains, then it could still be useful; that's a POOR too. Describe the problem you see.

 

NOT FOUND -- I can't find it. Describe how hard you looked or confused you were, e.g., "not found after 10 minute search; unable to recover because all witnesses are destroyed" or "not found; existence doubtful, entire area is now a new shopping mall."

 

DESTROYED -- We prefer the more optimistic "NOT FOUND" above unless you have direct first-hand evidence that the mark is completely obliterated. Getting a mark listed as destroyed requires submission of evidence (like a photo) and an e-mail.

 

 

Q. I heard the NGS said that they don't want benchmarks reported more than once a year. Does that mean I need to report them every year?

 

A. No. You need to use your judgment on when it is a good idea to submit a report. If the last time the mark was found was 20 years ago (or anything more than a few years), then yes, report it, even if nothing has changed in the description. If it was reported last year but something major has changed (like, the name of road it is nearby has changed), then report it to help someone else find the mark. Think about how you would feel if you had that data sheet and wanted to find the mark--if it was set in 1942 and there were no recoveries since, would you feel confident of being able to find it easily? On the other hand, if there was a 2005 recovery that only stated that the mark was found as described, you would believe you could locate it with little problem.

 

Q. What sort of description changes should I report?

 

A. Any changes in the description should be reported. For example, changes in the name of the county, town or city where the mark is located. Maybe the “large Oak” the mark was in front of was cut down. Again, think of what YOU would want if you were looking for the mark. Measure from nearby landmarks--telephone poles, curb, road center, large trees, house corners, etc.

 

Q. What is the difference between the reporting to GeoCaching.com and NGS? Are the criteria for a find and a not found different?

 

A. Yes.

For a Found: GeoCaching.com wants to hear about every find. NGS only wants to hear about finds where the monument has not been found in 12 months or there is some change.

Not Found: For GeoCaching.com, this is a fairly causal rating. For NGS, professionals might spend extra time and money to use a more distant mark if they believe your report, so this rating shouldn't be given unless a serious and competent attempt was made to find it.

 

Destroyed: For GeoCaching.com, you are essentially recommending that hobbyists not waste their time looking for this. For NGS, the way to report it is different, and you are so sure it is destroyed, you are suggesting to professionals that they would be better off spending thousands of dollars establishing a new monument rather than bothering to look for the destroyed one.

 

 

Q. I found a mark and its horizontal coordinates were way off. I have the coordinates from my GPS for this mark. Does NGS want them? What format should I use to report the coordinates to the NGS?

 

A. This is a bit technical, so please read carefully. NGS has two different types of marks. One type of mark is used for vertical (i.e. elevation) control. These marks often have a “SCALED” position. If this is the case the datasheet will say so. A “SCALED” position means that the marks horizontal (LAT/LONG) coordinates were estimated using a map. In this case (and ONLY in the case), your handheld coordinates are potentially more accurate than the position listed on the datasheet. As such, please record your GPRr coordinates for the mark and include them in the notes of your recovery form. Although the Geocaching site uses the DDD MM.MMM format, here at the NGS we prefer that you use the DDD MM SS.S format. Also, please be sure to use the NAD 83 datum.

 

 

Q. I happened upon a benchmark, but it isn't listed on Geocaching.com. Can I report it to the NGS?

 

A. The Geocaching.com database is NOT the same as the NGS database. If you are going to be submitting recoveries, please use the NGS database to check the most up to date datasheet before you submit a recovery.

Not all marks in the NGS database are in the Geocaching.com database. If you do find a mark, and can’t find it on Geocaching.com, use whatever information you have about the mark (such as its coordinates, station name, or county) to look for it in the NGS datasheet database. The NGS database can be found at http://www.ngs.noaa.gov/cgi-bin/datasheet.prl.

 

 

* All of the questions and answers in the pinned thread from Deb on the main Benchmark forum would be good ones to include, too.

 

Q: I found a PID a couple years or so ago and logged it on the Geocaching site. Should I submit a mark recovery on the NGS site?

 

A: That depends. Check on the NGS database (NOT the gecaching.com database) and see if the mark has been recovered in the part 12 months. If you choose to submit a mark recovery, in the entry box called "Enter date of recovery", you must enter the date you found the disk, not the date you submit the mark recovery.

 

Q: I found an error on the datasheet. What should I do?

A: We would love to hear what the error is. To report it, don’t submit an update, but instead send an e-mail to cheryl.malone@noaa.gov

[caseyb]

I am hoping for comments and suggestions etc

 

My plan is to get feedback, make changes and then create a new thread, lock it, and pin it to the top of this forum.

 

-Casey-

[+bicknell]

Looks good, I still want to know:

 

Q. Does anyone repair / reset damaged marks?

[caseyb]

Looks good, I still want to know:

 

Q. Does anyone repair / reset damaged marks?

Not really. We used to do stuff like that, but we no longer have the staff for it. It may happen under certain circumstances, but fixing a monument is going to be an exception to the rule.

 

Other agencies may do it. Like if a DOT destroys a mark, they may set a new one, or attempt to replair a damaged one.

[+Black Dog Trackers]

In the definition of POOR, I think that this beginning phrase

If the mark is scarred and leaning,

should say instead:

 

If the mark is leaning over to the side,

 

and change the defintion of GOOD to:

 

GOOD -- Recovered as described on the datasheet, and looks like it has not been moved or tilted. Even if the disk face is marked up, if the stamping is good enough to identify the station by name, it is GOOD.

 

as per this quote:

DebBrown

Posted: Apr 9 2004, 12:55 PM

 

If a setting is stable and the stamping is good enough to identify the station by name but the disk face is marked up I'd call it GOOD.

[Wintertime]

This looks really good, Casey. I like the friendly tone. Next time I find a mark, I will note whether it looks "healthy and happy." :-)

 

A few quick comments:

 

Not Found: For GeoCaching.com, this is a fairly causal rating. For NGS, professionals might spend extra time and money to use a more distant mark if they believe your report, so this rating shouldn't be given unless a serious and competent attempt was made to find it.

I think you meant to say "casual" rather than "causal." The latter doesn't seem to apply in this context.

 

A. This is a bit technical, so please read carefully.  NGS has two different types of marks.  One type of mark is used for vertical (i.e. elevation) control. These marks often have a “SCALED” position.  If this is the case the datasheet will say so. A “SCALED” position means that the marks horizontal (LAT/LONG) coordinates were estimated using a map. 

I'd explicitly say that the two kinds of marks are horizontal and vertical (elevation) control marks, then continue with the above information about scaled positions. I would also add an explanation of adjusted positions.

 

Although the Geocaching site uses the DDD MM.MMM format, here at the NGS we prefer that you use the DDD MM SS.S format. Also, please be sure to use the NAD 83 datum.

I think this information should have its own question. It's an important topic. E.g., "Which coordinate system should I use when I report a mark to the NGS?" Also, isn't NAD83 the same as WGS84? I believe it's common for consumer-grade GPS receivers to use the latter, so perhaps you could say "use the NAD83/WGS84 datum" so that folks won't think they have to change models when they switch between geocaching and benchmark hunting.

 

* All of the questions and answers in the pinned thread from Deb on the main Benchmark forum would be good ones to include, too.

Looks like you brought in a couple of them. I presume the others were already answered elsewhere in the FAQ?

 

Thanks for doing this, Casey!

 

Patty

[evenfall]

Hi Patty,

 

I am glad you asked this as it really is a common misconception. The way Casey addressed that is right on. The NGS is looking for us to do things a certain way, and for very good reason.

 

"Also, isn't NAD83 the same as WGS84? I believe it's common for consumer-grade GPS receivers to use the latter, so perhaps you could say "use the NAD83/WGS84 datum" so that folks won't think they have to change models when they switch between geocaching and benchmark hunting."

 

Nope, they are not the same, and at the geodetic level, very not the same. Sorry, People really need to change the Datum to do NGS work. And we need to educate this so people will know to toggle back and forth. Degrees Minutes and Seconds are the method NGS prefers to annotate as it is the way Survey instruments work. This is the age old method. It is best to work in the traditional way that survey equipment works.

 

Please feel free to call me an alarmist Surveyor if you like. :-D I have written exhaustively against the use of the WGS 84 Datum for this work and if you look back through my posts on my user profile page you can read what I have said about it in a number of places. I have attempted to express what the differences are and why I feel this is a bad idea. I have a number of friends in the field, and some who work at NGS who agree.

 

For a quick look, here is one I posted in the NGS Forum: http://forums.Groundspeak.com/GC/index.php...dpost&p=1378019

 

I know that if we grab an FAA chart, it will say NAD83/WGS84 Datum. In an airplane it is close enough... They are dealing with large distances. Both datum are similar enough at that level to be the same. An airplane is way larger than the difference between datum. We unfortunately are not working in the same scale. We are dealing directly with the objects that help define what the NAD83 Datum is. Some are less than one centimeter accuracy. They are not expressed by WGS84 in any way, in fact expressing their location in WGS 84 would introduce error. There is a 1 meter difference between the two datum taken spherically in three dimensions, and at the level we work, it can make a difference. To the airplane that is the size of carry on baggage. It really would make a difference if and I say it could happen, if consumer gear were to become even more accurate than it is. You never know.

 

Sorry, But the correct datum is not that hard to use, and important when doing NGS work. NAD83 is the only Datum.

 

WGS84 will work for Geocaching and even for getting you close to the where of a Benchmark for playing the game, but the real Datum is the NGS owned and developed NAD83 Datum for use on their proprietary Survey Markers.

 

Rob

[caseyb]

Nope, they are not the same, and at the geodetic level, very not the same. Sorry, People really need to change the Datum to do NGS work. And we need to educate this so people will know to toggle back and forth.

While this is of course technically correct, I am thinking that for the purposes of the FAQ, I am going to not address this issue. Simply put, I want to keep the FAQ as simple as possible. Handheld GRSr generally do not have the accuracy required to notice a difference between NAD83 and WGS84. And more importantly, nobody is going to be using the reported handheld coordinates for anything other than locating the disc.

 

For the record, use NAD83 if you know how to switch datums. If you dont know how to switch datums, or dont want to, dont worry about it, as it is not going to really make any significant difference for benchamark hunting.

 

-Casey-

[caseyb]

* All of the questions and answers in the pinned thread from Deb on the main Benchmark forum would be good ones to include, too.

Looks like you brought in a couple of them. I presume the others were already answered elsewhere in the FAQ?

Good suggestions! And thanks for catching that typo.

 

I am not going to address ALL of the questions from the other thread in the benchmark hunting forum. Some of them are way too technical for a general FAQ. My purpose it to answer FREQUENTLY asked questions.... not every question ever asked. If you feel there is one particular question that is often asked and needs to be addressed, please let me know.

 

 

-Casey-

[evenfall]

caseyb Posted on Apr 5 2005, 10:38 AM

For the record, use NAD83 if you know how to switch datums. If you dont know how to switch datums, or dont want to, dont worry about it, as it is not going to really make any significant difference for benchamark hunting.

 

I digress.

 

So Ah, Datum Schmatum, and Official NGS recovery now = geocaching. You can treat it the same as the game.

 

For the record, This seems to be an interesting new NGS Sanctioned direction.

 

I have always wanted to file an official not found on the Seattle Space Needle in the WGS72 Datum... Or, Whatever_Datum_I_Want! Just because I could. I was getting tired of walking the line, and Now I can! It isn't significant and No one will worry about it! Lucky Me! I wonder if it is healthy and happy? Is there a radio button for that on the Mark Recovery Entry Page?

 

I feel so free!

 

Ya think?

 

Sure will make all this technical crap a lot easier. We no longer have to care!

 

Now I can get back to my true focus of extolling the Virtues of red and white striped chaining pins! Yeah!

 

Rob

Edited April 6, 2005 by evenfall

[2oldfarts (the rockhounders)]

caseyb Posted on Apr 5 2005, 10:38 AM

For the record, use NAD83 if you know how to switch datums. If you dont know how to switch datums, or dont want to, dont worry about it, as it is not going to really make any significant difference for benchamark hunting.

 

I digress.

 

So Ah, Datum Schmatum, and Official NGS recovery now = geocaching. You can treat it the same as the game.

 

For the record, This seems to be an interesting new NGS Sanctioned direction.

 

I have always wanted to file an official not found on the Seattle Space Needle in the WGS72 Datum... Or, Whatever_Datum_I_Want! Just because I could. I was getting tired of walking the line, and Now I can! It isn't significant and No one will worry about it! Lucky Me! I wonder if it is healthy and happy? Is there a radio button for that on the Mark Recovery Entry Page?

 

I feel so free!

 

Ya think?

 

Sure will make all this technical crap a lot easier. We no longer have to care!

 

Now I can get back to my true focus of extolling the Virtues of red and white striped chaining pins! Yeah!

 

Rob

 

Rob,

 

Handheld coordinates are for getting the surveyor to the correct area. It is 'assumed' that said surveyor will be able to look around at that point an located the benchmark. It will typically get the surveyor with-in 15 feet (and less, usually) of the mark and unless he is blind and can not follow the rest of the description, he should be able to walk right to it.

 

Handheld coordinates are an AID in LOCATING the disk and not for 'occupying' the station.

 

John

[evenfall]

John,

 

I do understand what you are saying. I appreciate that you are trying to point this out. And you are not even technically wrong in the context of what we are doing. But there is a bad habit that can develop from thinking this way, and that is what I had hoped to avoid.

 

My interest in this matter goes a bit beyond the obvious. A datum in and unto itself is a difficult thing to get ones mind around, and to add difficulty to that, people as a general way of being, filter information and remember it in generalized ways. We never know who will read this or what the concept is that they my have or understand. What I mean is that if someone who is thought of as an authority on something, or even just a really convincing person is to be heard saying that something is this way or that, Even in a certain specific context, the listener and their filter will tend to omit some specifics and then take what is to be remembered and generalize it the rest of the way. Then they will tell ten other people that their generalized understanding is the gospel truth. Their Listeners won't know any different, and won't know that what they have been told is a generalization, Not the actual situation or information.

 

This happens all the time. But I feel we have the opportunity to teach a better way of thinking and approaching this.

 

The survey field is literally awash with things that hard to understand, and that don't always make sense, but even still it is a science. One of the warts we see is that it is a general misconception among people that WGS84 and NAD83 are fully interchangeable. Some even think that a Datum is inconsequential. Generally Speaking, even while this is never technically true, to most, in the lay person category and even some professions, the difference does not matter. Still, after the "is it bigger than a bread box" test is applied, It is an erroneous construct. An improper belief.

 

When we are dealing with Datum at this level, Which I mean for us to understand as the level we are working with here at geocaching, when recovering Survey markers to the NGS, it is safer, and just plain good practice to be as correct as we can. There is nobody standing over us with a stick here, but we should take it upon ourselves to go that extra mile, because we actually are dealing directly with the objects that physically represent the Datum itself. There are many things we discuss that would be technically incorrect if we do not observe this. And Scarier still to allow people to regard Datum data as not a big deal. It is safe to say that some people may think I am making a big deal out of that, I am, and just because the tendency of human Nature is to over simplify and disregard what seems too difficult to otherwise do. I am also saying that it is not always in our best interests to oversimplify, especially when this really isn't that hard in the first place.

 

My premise is to help everyone understand that there is importance here. We are dealing at a level where the Datum really does matter and that we should endeavor to understand this as well as we can. We have a great opportunity in this forum to teach things in the correct way up front. I cannot affect how you chose to believe or remember, all I can do is tell you what we in the field feel is currently known and widely held as true.

 

It does not seem beneficial to say what we have said and leave the general reader with the impression that NAD83=WGS84. It does not equal, not really, and since we are dealing with the differences even in discussion at a geodetic level, then I feel very not really.

 

The understanding is safer when we just follow the age old advice of making sure you are working in the Datum on the Map or that which is listed as the correct Datum for the work we are doing, Rather than dumbing it down so that is is simple and easy. If it were simple and easy, we would not have the system we have. I trust that the Pros who work at that level wish it were simple too.

 

Casey said earlier in this thread that the NAD83 Datum would be the preferred Datum. He has since reversed himself. As an Official employee of the NGS I wish he had stuck with his Agencies own Datum and the first thing he said. He is missing a wonderful opportunity to help his agency put to rest some widely held misconceptions about what the NGS and their Datums are for. Especially the one that points out why the NGS does not use WGS84 in the first place. The NGS developed and own NAD83. It is the only Horizontal Datum they currently use. At this level of thinking and activity, it is important to have a correct understanding. It is the right thing to do.

 

Just my.02

 

Rob

[2oldfarts (the rockhounders)]

Rob,

 

You seem to have a hard time understanding that the difference between NAD83 & WGS84 is irrelevent in this context. When I find a benchmark and have my GPSr set to NAD 83 it reads the SAME as WGS 84. Check some of the pictures from benchmarks I have found. Quite a few of the show the GPSr with WGS 84 as the primary Datum at the top of the screen and NAD 83 as the secondary datum near the bottom of the screen.

 

There is NO way you would know which datum I was using unless I specfied. At this point they ARE identical. If I had a $25,000 GPSr it would be different, but given very few Geocachers can afford this type of unit for play, it becomes moot as to which Datum you submit your report in.

 

To think that there is enough of a difference in the 2 datums that it will make a difference when someone else uses them to FIND the benchmark is ludicrous! With the difference between the datums being as small as it is and the Position Error of the handheld being as large as it is, Demanding that people only use NAD 83 is - plain and simple - bad judgement on your part. If you can NOT find a disk using WGS 84 then what makes you think you will find it using NAD 83, especially when the Position error is in the 15' to 20' range on the handheld GPSr?

 

Lighten up and cut Casey some slack here. He's trying to get this forum up and running so that the AVERAGE user will be able to understand benchmarking and be able to log with the NGS if they so desire.

 

John

[evenfall]

John,

 

You think this is riduiculous? Was that you flaming me? :-D This makes NGS recovery equal Geocaching. Period. There is nothing further needing said. I mean you know that since you are in Arizona, that what goes in Arizona, Goes in all America, You are sure. Arizona = America? The people on the N. Slope in Alaska hope you are right.

 

The Western United States especially in Vertical Movement is Undergoing Volatile moment which is in the multiple meter range in some places. This is something that WGS 84 does not even track. These Vertical anomalies can force changes to previously located Horizontal Positions. However The NAD 83 Datum adjusts for this.

 

Why will NGS be developing the NAD 83 (2006) Datum if nothing has changed?

 

Besides John, you have been opposed to this Forum from the very beginning, and you are not interested in NGS recovery. I don't see how this is your issue or why you would choose to become involved in it. If you want to take issue with me, The email is the most appropriate format for doing so.

 

This in answer to you is worth repeating. I only need to quote myself from earlier in this thread.

 

I digress.

 

So Ah, Datum Schmatum, and Official NGS recovery now = geocaching. You can treat it the same as the game.

 

For the record, This seems to be an interesting new NGS Sanctioned direction.

 

I have always wanted to file an official not found on the Seattle Space Needle in the WGS72 Datum... Or, Whatever_Datum_I_Want! Just because I could. I was getting tired of walking the line, and Now I can! It isn't significant and No one will worry about it! Lucky Me! I wonder if it is healthy and happy? Is there a radio button for that on the Mark Recovery Entry Page?

 

I feel so free!

 

Ya think?

 

Sure will make all this technical crap a lot easier. We no longer have to care!

 

Now I can get back to my true focus of extolling the Virtues of red and white striped chaining pins! Yeah!

 

Rob

Edited April 6, 2005 by evenfall

[2oldfarts (the rockhounders)]

Rob,

 

You missed the point again! The purpose of posting handheld coordinates is to assist the "Surveyor" in locating a disk he wishes to use. If he can NOT find the disk using a handheld GPSr using WGS 84 then there is little chance he can find his way home from work.

 

We are not talking doing a survey quality position here, just something to help get the "surveyor" to the right place and reduce the amount of Time needed to "Occupy the Station".

 

The difference between NAD 83 and WGS 84 is lost in the amount of GPSr position error and at that point it becomes moot as to which datum is used for reporting the find.

 

If the 2 datums are different by .0015 MINUTES then the error position of the GPSr masks that difference and the surveyor can still go to those coordinates and find the benchmark. If he can read a handheld GPSr - that is.

 

The average position error of a handheld GPSr is considered ABOUT 20 feet. The difference between the datums is considerably less than that, SO You have just canceled the difference between the 2 datums.

 

As to the crustal movements, the only way to know how much has occured is to occupy the station and measure it. That is not what we are doing. We are trying to get the surveyor close enough to the correct position so he can locate the disk.

 

If I enter the NAD 83 coordinates from the NGS datasheet they will be off just like the WGS84 coordinates since it has not been updated since the movement has occured.

 

If it offends you that others can understand the purpose of using handheld GPSrs and you don't, well, such is life......

 

John

[+BuckBrooke]

Well, I'll step into the middle of this conversation for a moment. I'm a 26 year old Physics PhD student at the University of New Mexico in Albuquerque, NM. I've been benchmarking for 6 months or so, seriously for the last 4 months. I understand much of the physics behind the GPS system without the technical knowledge that is needed for a professional surveyor.

 

The point that I would like to make is that I fall into the mid-range category of benchmarkers here.

 

The intro level is Geocachers who find a mark (or something else, or the RM, or whatever) and log it as a find on geocaching.com. Many don't care about the accuracy of their find, and they usually though not always provide useful information in their reports.

 

Then there are the mid-range people like myself who consider themselves benchmarkers rather than geocachers. Some of us have more equipment, or less, and some of us report to the NGS. I report all of my finds, not finds and ask Cheryl/Debbie about destroyed marks. I take pains to accurately report, knowingly taking into account my lack of qualifications and experience in surveying. I am intrigued by the technical discussions of surveying, and while it gives me an appreciation for the professional efforts involved (that makes me work on recovering marks accurately) I'm more interested in the human aspect of surveying and the expeditions involved. Barring battery failure, I take photos at each station I find that are probably good enough for NGS, and report at both geocaching and the NGS database, so that people who use either site can benefit.

 

Then there are the advanced range group, those who are or once were surveyors, who have done this for a living and know all about it. They will generally go to greater efforts to find stations that have been lost, and view benchmarking as a challenge to use and hone their skills. They often provide information and drive discussions in the forums that educate the rest of us.

 

I, like many of the people here, have not been trained and are doing this as a hobby. That doesn't detract from our ability to accurately report to the NGS, as long as we are careful in listing NOT FOUNDS, take the time to verify our FOUNDS, and make accurate TO FIND reports where needed. Oh, and we say we're not sure when asked about satellite coverage. If we do that, even if we're reporting a SCALED station that could use more accurate coordinates, at the end of the day our reports should be as close as we can get to someone who knows a lot more about the process than we do.

We won't give inaccurate reports, and what we say will be good enough for the next person to find the station, set up their transmitters/receivers/theodolites and get to work.

 

And that's what we can and should contribute. You can't get more out of me; I simply don't have the time. I have to say that the Datum discussion simply doesn't enter into my reporting stations to the NGS. It may be important to my understanding of surveying and the process of geodetics, but it doesn't matter on what I add to a station's datasheet. If the station is ADJUSTED, I don't enter coordinates, as in my experience they're always accurate within my GPS error. If it's SCALED, then my GPS unit will get close enough in whatever datum that it doesn't matter, as the next fellow to use the station won't use my coordinates. After all, the NGS is listing them as Handheld Unit coordinates, so a pro will take them with a grain of salt.

 

I think we need to separate the aspects of training benchmarkers to be effective and contributing members of this community from the educational, technical, optional aspects of education about the field. Let's train people to go out, find stations and report accurately. Let's ease them into the addiction.

[+Black Dog Trackers]

Yo, evenfall - We must remember that people submitting handheld GPS measurements is simply an augmentation of the to-reach information. I don't see any surveyors giving to-reach measurements to the nearest millimeter.

 

I think caseyb's post is right in tune with the NGS wanting to get better to-reach information from us without being too overbearing (pun intended).

Edited April 7, 2005 by Black Dog Trackers

[Bill93]

The measurement is as useful in WGS84, but the FAQ should still encourage (not require) use of NAD83 since it is the "right" datum. I set mine on NAD83 and leave it there for everything.

[GH55]

Submitting NGS recovery means we get to add a small part to the work of the NGS. That work uses NAD 83 in DD MM SS.S.

 

Those are the standards. I see no value in persisting in doing it incorrectly, whether or not the error introduced in each report is less than the expected error in the measurement.

 

Do you have NAD 83 in DD MM SS.S available in your GPSr unit? Then to use other units and another datum for NGS recovery reports is simply wrong. There is a learning curve to this activity and mistakes will be made. But for those who know the NGS standards and practices, to use other units and/or another datum is to be wrong on purpose.

 

That should be the end of the discussion if your purpose in making recoveries is to help NGS in their work.

 

The FAQ could simply state: NGS uses the NAD 83 datum. Coordinates are recorded as DD MM SS.S. Recovery reports which include GPS readings should conform to those standards.

[evenfall]

John,

 

Again, I really have to wonder what end justifies your means. You were vehemently opposed to this Forum yet here you are... Again.

 

I can't help but chuckle John. But I cannot take you seriously. Sorry John, Everything you say in here is lost on me. You may as well just say nothing at all, as I have tired of you having nothing nice to say. You will get further with me by saying nothing at all. I am not going to wade into it with you. I have offered to you many times the opportunity to contact me off the forum and you have chosen not to, as well as not to reply to my two attempts to contact you off forum. So I think I just put a fork in that eh? Done. :-) I wish you all the best with the Geodetic Interactive Spatial Referencing Devices thread in the other Forum. Going forward, You will be safe from my thoughts in there.

 

As for everyone else, Thank you for your inputs and concerns. I do understand what you are trying to say, and I considered this, While you all make a good point, and a point well taken, the only official Horizontal Datum the NGS has is NAD 83. I am sorry that other Datums are close enough for whatever reason, but this is NGS work. We can avoid getting confused ever, if we try standardizing our practices, even when close seems close enough. Things are confusing enough.

 

Intermixing these Datum can cause a lot more confusion that people think, This Confusion is not in my imagination either. I have seen it before. Been there. Washed my Truck with the T-shirt. It really is worthwhile to keep like with like. It is part of every surveyors work to deal with these things this way, and this is something that is part of that world. I am not saying anyone is wrong here, nor am I trying to back away from what I believe. But why not just follow the code. Why open the geocacher to the scrutiny that the Power Squadron has had put upon them. Integrity is made by following Standards.

 

Buck had a very Salient point, in a very well thought out post. He feels he is somewhere along the growth phase of what a Benchmark hunter knows and understands. I am not anyones' Judge so I won't go there. But what I do want is for people to be Taught what is correct in the first place, If after they understand what is really what, and they want to play fast and loose with things, I cannot stop them, But they will know what was correct to the best of my knowledge if they learned it from me.

 

It appears to me that Many People may really just want to do what they want because they are resistant and because the don't want to have to follow any form of direction. I hope I am wrong.

 

Why is simply toggling your GPS to NAD 83 such a big deal? If we made any mistake from there, we sure would not have to explain that error, eh? If we cannot agree that a new Geocacher beginner bench marker is someone some would not feel comfortable working on a State Project in Wisconsin, Are we so sure we want to ask people to report things to the NGS when they don't understand how to toggle between Datum on their handheld? C'mon, I think we know that there are different Datum for different Purposes, and we know which ones we would be correct to use.

 

WGS 84 is for Geocaching. I don't see anyone contesting that. If it is no biggie, then why would Geocaching bother to specify which Datum they are using? The NGS is 200 years old, they have their Datum too. It is what it is, and you all may do as you like, but I feel it is important and that is where I come down on it.

 

As always,

 

Rob

Edited April 7, 2005 by evenfall

[2oldfarts (the rockhounders)]

Geocaching specifies WGS 84 because the predominate map datum is NAD 27.

 

Am I prohibited from using "your" forum?

[+Klemmer]

Now I remember why I stopped reading all the GC forums except Benchmarks & NGS. Lighten up, guys! Both of you.

[evenfall]

Heck No John,

 

I would never think of asking you to take you ball and go home, I own nothing, This Forum is not mine at all, it is for everyone, and NGS recovery, The more highly Technical stuff. I wanted it for all of us, But you were very adamantly against this, so why else would I be inclined to wonder what your motive is? If you came here because you see an opportunity to argue with me. Sorry. That is not going to happen. It isn't constructive. The other people here do not deserve to read the way you seem to choose to approach me. I feel it doesn't respect them.

 

I am sensitive to what is going on. and not just with you and I. Basically it is just that I am tired of arguing with you. I say Tomato and you say Tomahto... It always seems to wind up that way, and there never seems to be a way to lift anything up from it. It always seems that when you post in response to what I have said, I feel it is filled with snide comments and innuendoes. That isn't my style and I don't appreciate it from you. Other people disagree with me but they refrain from personalizing it. and that is nothing more than a Healthy debate and a proper usage for a forum. I am not always right nor do I expect everyone to agree. Since you only do this in regard to me "in Forum", I have no choice other than to address you in forum. I just agree we always disagree for whatever reason and there is not further any need to belabor it. All I am saying is that if you want to go to your pinned thread and teach that the Moon is made from Green Cheese, In your own words, Be my guest. Say it here, I'll likely debate you.

 

You may even disagree with how I see this, but it is what it is. Feel free to enjoy all the forums as you like. Just know that I won't be over at that pinned thread, taking taking you to task over whatever. I think you are doing a good Job, You just do it your way. If you want to get beginning hunters off to a good start and you feel that keeping it simple is a good approach, I agree, there are a lot of people, which you have and will help with your way or methods. After awhile some people choose to delve deeper, It can become technical and involve a lengthier explanation. I actually try to come to the same side of the table. I don't Lecture, Talk at or to people, I like going with the "I am with you on this" approach. It might be unseemly, but not everyone gets all they want from simple explanations. Different strokes.

 

If you were to know me, you would find that I am really just Rob of the corner, but that doesn't matter much now. Regarding my point, well I have exhaustively made it. We can re read it or not, but that is my take on it. Obviously I feel as I do about it. I stand for what I believe. I would not have said it if I didn't think my position had no basis. There is nothing wrong with speaking ones mind.

 

P.S. Thanks Klemmer, Good advice.

 

Rob

Edited April 7, 2005 by evenfall

[Wintertime]

Maybe I'll switch my GPSr to NAD83 and leave it there, too. But I'll be interested to see whether it makes any difference in the readings I get with a $400 GPSr.

 

Before I posted that comment, I checked a few sites to verify my memory that the two datums were used in the same breath even in some professional applications. And indeed, I found some such references, including an NPS report on understanding datums for GIS work that says, "The differences between these two datums for North America is not discernible with mapping/GIS grade or consumer grade GPS equipment," and a mention on a GIS software web site that, "Almost all the transformations between NAD83 and WGS84 have zeroes for the parameters. I think there is one for the Aleutians that has nonzero values." So I completely understand why Casey says he isn't going to worry if geocachers submit reports to NGS that are based on WGS84 readings.

 

Back to the original topic of the FAQ...does anyone see any obvious omissions? Casey, I will double check the old discussions with Deb, but I see your point that you don't want to get into gory details in a friendly introductory FAQ, so you've probably gleaned the important topics from those discussions already.

 

Patty

Edited April 7, 2005 by Wintertime

[kc2ixe]

Hey, I'll add my 2 bits. About 50% of the time I've gone out hunting, I don't even BRING the GPSr. What datum should I use ?

 

So far, at least around here, even the adjusted marks are right on the money withing the accuracy of my GPSr. Probably because I'm on a street grid, and it was fairly easy for the guys monumenting the disks to measure off the map

 

I will admit that MOST of the stations I go hunting are intersection stations I KNOW are gone. Many of them I saw get torn down when I was younger, and it's a matter of digging up PROOF that they are gone. The advantage to living in the same place for more than 40 years (or in the case of my parents, 50+ in this house, and 70+ in the neighborhood) is that you KNOW where most of the intersection stations are/were, and can remember the ones that are gone. The disadvantage is that in general, the neighborhood isn't getting BETTER

[caseyb]

My goodness.

 

This thread has been officially hijacked. I have to say I am a bit disappointed. I was really hoping to get some good feedback on the FAQ.... not an intense, person debate and flame session like I just saw.

 

Even my post was taken totally out of context. So for the point of clarity, let me re-state what I already wrote:

 

"For the record, use NAD83 if you know how to switch datums."

 

I never "reversed myself". My only point was that just because some people don't know how to switch Datums, and/or are not interested in doing so, that does not mean they cannot fully participate in submitting recoveries to NGS. In a sense the datum is irrelevant in that you don't even need to submit the coordinates of a mark! Just let us know if it is there! Handheld coordinates are a bonus (which we are very thankful for), not a requirement.

 

This thread is something of an embarrassment at this point. I was really hoping we were above this type of exchange. I am not a moderator around here, but I did start this thread. So I am now closing it. If you have any other thoughts and comments about the FAQ, please send me an e-mail.

 

-Casey-