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RTK Part 2

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(@mightymoe)
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following an RTK survey from 1997:

I'm locating existing monuments set in 1997 along a deed/fence line, they are checking very well, so I cut across from one end of the fence line survey to the other and looked at the resulting numbers disregarding surface and grid values

2014:

NS Fwd Azimuth 147-49-39.4, Ground Distance 24333.07'

1997:

NS Fwd Azimuth 147-49-39.2, Ground Distance 24333.06'

Dang!!!!;-)

Of course the RTK system in 1997 was "crude" compared to the R-10 used for the 2014 survey, but still very effective

 
Posted : January 8, 2015 7:29 am
(@jimmy-cleveland)
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Sounds like pretty good work. Congratulations

 
Posted : January 8, 2015 7:37 am
(@shawn-billings)
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Agreement in measurements is really quite trivial considering the actual meaningful data any competent surveyor should be considering are the realistic error estimates for each observation. I'm quite certain that the error estimates from the 1997 survey properly adjusted in a quality least squares program, such as Star*Net, with the 2014 survey data, will prove you are an idiot.

If one believes that obtaining sub-centimeter repeatability between two monuments separated by 4.5 miles is anything other than common fare, I'm afraid I couldn't possibly enlighten such ignorance.

Best Regards.

 
Posted : January 8, 2015 7:42 am
(@paden-cash)
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you kids be nice now...;-)

 
Posted : January 8, 2015 7:52 am
(@shawn-billings)
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yes sir, Uncle Paden.

:whistle:

 
Posted : January 8, 2015 8:01 am
(@kent-mcmillan)
Posts: 11419
 

GPS Part 2

> Of course the RTK system in 1997 was "crude" compared to the R-10 used for the 2014 survey, but still very effective

So, you're amazed that GPS positioning works, particularly in wide open spaces? What was the uncertainty in the bearing and distance you inversed between the two points or do you know?

The real story with RTK has always been that it is the GPS method of choice for the clueless. You're checking a survey made by GPS (probably involving long occupations in 1997) and seem to be marvelling that it worked. I just finished following a survey made by RTK in 2013 that had busts of more than three feet in under half a mile and decimeter errors scattered throughout, almost certainly as a result of user cluelessness.

 
Posted : January 8, 2015 8:33 am
(@mightymoe)
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GPS Part 2

I just finished following a survey made by RTK in 2013 that had busts of more than three feet in under half a mile and decimeter errors scattered throughout, almost certainly as a result of user cluelessness.

That's a shame:-O

 
Posted : January 8, 2015 8:45 am
(@kent-mcmillan)
Posts: 11419
 

GPS Part 2

> I just finished following a survey made by RTK in 2013 that had busts of more than three feet in under half a mile and decimeter errors scattered throughout, almost certainly as a result of user cluelessness.
>
> That's a shame:-O

Since your work is probably in close to optimal conditions, not much brush above tripod height, that isn't much of a challenge to GPS use. What typically happens with the RTK users is that they tend to use it even in places no experienced GPS user would consider: beside trees, under dense canopy, etc. Add to the mix the fact that they bought RTK in order to do the work on the run and it's amazing that RTK surveys ever look even semi-pro.

 
Posted : January 8, 2015 8:58 am
(@shawn-billings)
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GPS Part 2

What was the uncertainty in the bearing and distance you inversed between the two points or do you know?

Translation: Residuals don't matter - what's the error estimate?

I just finished following a survey made by RTK in 2013 that had busts of more than three feet in under half a mile and decimeter errors scattered throughout, almost certainly as a result of user cluelessness.

Translation: RTK sucks. Look at these observed residuals.

RTK has always been that it is the GPS method of choice for the clueless.

Translation: You're clueless.

all too predictable.

 
Posted : January 8, 2015 9:08 am
(@the-pseudo-ranger)
Posts: 2369
 

Wow. I always thought you were more level headed than this. GPS is a nice tool to measure two points 4.5 miles with repeatability. I'd argue that if two surveyors, 20 years apart, produce nearly identical results over 4.5 miles, it's a sign that both surveyors knew what they were doing and followed good procedures ... not really the sign of ignorant idiots.

 
Posted : January 8, 2015 9:27 am
(@mightymoe)
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By comparing actual results you are doing irreperable harm to the very fabric of society

I know, I know silly me, I keep comparing actual field measurements. I really, really have to stop doing that:whistle:

 
Posted : January 8, 2015 9:31 am
(@shawn-billings)
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It was satire. I thought the "Best Regards" gave it away. I think those results are fantastic, particularly for a 1997 RTK survey.

 
Posted : January 8, 2015 9:36 am
(@mightymoe)
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I kinda figured Shawn, but I am clueless often:-P

 
Posted : January 8, 2015 9:42 am
(@kent-mcmillan)
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GPS Part 2

> What was the uncertainty in the bearing and distance you inversed between the two points or do you know?
>

> Translation: Residuals don't matter - what's the error estimate?

No, it means that if you don't know what the uncertainty in some results are, you really don't have any reliable basis for making a meaningful comparison. The revealing answer would be why most RTK users don't seem to be very sophisticated about uncertainty estimates.

> I just finished following a survey made by RTK in 2013 that had busts of more than three feet in under half a mile and decimeter errors scattered throughout, almost certainly as a result of user cluelessness.
>

> Translation: RTK sucks. Look at these observed residuals.

No, it means that large blunders like that are more typical of RTK work than with conventional survey and post-processed GPS.

>
> RTK has always been that it is the GPS method of choice for the clueless.
>

> Translation: You're clueless.

No, it just means the the odds of RTK being used cluelessly are surprisingly good. It's the Saturday Night Special of surveying technology at the moment.

 
Posted : January 8, 2015 9:42 am
(@the-pseudo-ranger)
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Sorry. It went over my head.

 
Posted : January 8, 2015 9:43 am
(@mightymoe)
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I do know a few guys who were always hung up on the measurements of their girlfriends, I can tell you from observations that [sarcasm]that always worked out well for them, lol[/sarcasm]:-X

 
Posted : January 8, 2015 9:49 am
(@shawn-billings)
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I thought I covered all of the bases pretty well:

1. Real world residuals don't matter (let's keep the facts out of this)
2. Star*Net
3. You're an idiot
4. Anybody can do that
5. RTK still sucks
6. You're an idiot

7. Star*Net

oh yeah, and...

8. Best Regards

Heck just look a couple of posts down and do a blind test. Can you tell the difference between my satirical post and Kent's sincere post?

 
Posted : January 8, 2015 9:52 am
(@paden-cash)
Posts: 11088
 

> What would be the uncertainty of a restaurant review written by a reviewer that has never eaten at said restaurant?

Kinda like a nun preaching that sex is bad because all they've ever seen or heard was bad things about it.

But, there's always a different point of view. Like I told Sister Mary Knucklesmacker in school: "The chances of me getting pregnant are pretty slim." B-)

 
Posted : January 8, 2015 9:53 am
(@lmbrls)
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GPS Part 2

> The real story with RTK has always been that it is the GPS method of choice for the clueless.

No argument about your statement. In fact, I have never used strictly RTK or GPS in general for a boundary survey. We just have too many trees in GA. I do use GPS to establish control for boundaries and design projects. Is the problem the methodology or the proceedure? I am in total agreement that positional certainty can not be determined by a single RTK observation. However, can you not determine positional certainty by redundant observation over a reasonable period of time?

My only point is bad procedure is bad procedure regardless of the method employed. I see many surveys that are screwed up without RTK. The great equipment we have today gives surveyorsequipment technicians the ability to screw up more data quicker than ever before.

 
Posted : January 8, 2015 9:57 am
(@mattharnett)
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LOL

> > It's the Saturday Night Special of surveying technology at the moment.

That's a good one.

:good:

 
Posted : January 8, 2015 10:09 am
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