This doesn't quite fall into the thread about poor boundary surveys, so new thread. It's probably a tech without a clue.
I'm looking at an NGS data sheet for a FBN/HARN that has a recovery report by an Engineering/Surveying company. The report gives their measurements in SPC to 0.0001 ft precision, with no notation on reported tolerance or even how derived. Really? Converted, they are 6.5 mm horizontal and 35 mm vertical different (using what geoid?) from the data sheet. My guess is RTK from the DOT network, but that's only a guess. Seems pretty useless to report it.
But the punchline is that besides SPC they give lat-lon which is several degrees different from the data sheet. In fact, as near as I can tell it is the 0-0 origin of the SPC (Corpscon won't compute it, but their data collector probably did).
It's pretty sad when someone doesn't have a clue what reasonable numbers are for their area of work, but much worse that they don't bother to compare to the published values and recognize a huge discrepancy before publishing.
What is the PID of the mark? I would like to look at the datasheet.
Thanks in advance.
Guess it doesn't hurt to list it.
http://www.ngs.noaa.gov/cgi-bin/ds_mark.prl?PidBox=le0188
To their credit, it had been 10 years since a recovery report, so it was good to note that it still appeared usable.
That's better than the one where someone used the GPS in his phone to send in a note that the datasheet was wrong.
Looks like they are dead on N-E, the elevation is probably like the N-E and derived from an OPUS report, .11' would be about the difference I would expect in my area.
Of course since it's a first order bench mark the elevation from GPS will be of lessor quality.
Clearly there is an issue with the Lat, Long., probably a cut/paste thing.
Not sure why they would publish new numbers on a HARN point.
I was field walking a survey some years back and noticed a surveyor (I think from a construction company) trying to get locked on with his GPS Rover. Mind you he was surrounded by 30 story buildings. He was there for what seemed to be an eternity at the same point. Mainly because I field walked my job, looked around at a potential scan, had coffee with a client and came back and he was still there. One of those guys that says to your most experienced party chief, "I know you're data is wrong because my controller says so."
It's a good thing bad coordinates aren't explosive. There would be a lot of "surveyors" walking around with missing fingers. 😉
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paden cash, post: 403911, member: 20 wrote: It's a good thing bad coordinates aren't explosive. There would be a lot of "surveyors" walking around with missing fingers. 😉
Best one I've heard all year!
Me. "What's the difference?"
T.C. Carroll "It's the difference between right and wrong!"
I'm afraid we have all become button pushers we have too many batteries in the field we no longer write notes in the field book if we can't push the button we go home it is what it is.
Tommy Young, post: 403877, member: 703 wrote: That's better than the one where someone used the GPS in his phone to send in a note that the datasheet was wrong.
The one? I've seen alot more than one of those.
Nate The Surveyor, post: 404178, member: 291 wrote: I'm afraid we have all become button pushers we have too many batteries in the field we no longer write notes in the field book if we can't push the button we go home it is what it is.
I'm happy to say we don't play that here. We're old, tired and grumpy but we still do good work...
I hate those exploding coordinates - I can't afford to lose any more digits.
Well, I guess I will have to admit. I am not REALLY altogether a button pusher. My Javad does not really have a keyboard. So, they are imitation buttons. But, it does have some buttons around the screen.
So, I'm just pushing fake or imitation buttons. Maybe someday, voice commands, will be implemented. I suspect it will be a little like "OK GOOGLE".
It'd be neat. "OK Mr. Javad, inverse" "Yes" "104 to 10" "OK".
It's not there yet.... I am not sure our operating systems are there either, but somebody somewhere is banging away on computer keyboards, and it is coming.
Nate