wingman1
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Its time to fly Brett French in with the gazette
Wilks brothers true colors are shining through.....
- Thread starter wingman1
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wingman1
New member
I have aerial overlays that match up with hunting maps chip. What a cover up by BLM.
That's what onXmaps is- data from cadastral symbolized for display on the GPS unit. Could be inherent error of the unit or error in the base map that's produced from that cadastral data. Or both.
RobG
Well-known member
It is starting to make sense to me. The GPS is accurate at finding your location, but the map data that shows land ownership could be off. I wonder if you can get coordinates of the corners at the courthouse.
Your overlays probably use the same source as the gps maps do, so they'd reflect the same. IF the Wilks did get it surveyed, then that should be confirmed by the BLM. That "indicates that it likely was" in the article is BS.
If the Wilks are up to no good then I hope they get their asses handed to them, but I'm telling you from personal experience, that GIS boundary can't be trusted that accurately, it needs to be surveyed.
fowladdict
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As a Land Surveyor I can say Randy has this right. The day all GIS data is accurate on hand helds will be the day I no longer have a job...an exaggeration yet some truth. I have documented our hand helds being as far off as 100-something feet from a found section corner when comparing with 25000 dollar surveying gps equipment.
fowladdict
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Highly unlikely. It is somewhat becoming a requirement within certain agencies that surveyors provide enough "survey data" so GIS departments can be a little more accurate with their boundary data. Your hand held will only get you close. How you define close is up to you.
Yikes fowladdict I don't want to think about that in light of corner crossing threads.
bobbydean
Well-known member
There was a cash exchange. GPS works the same . private or government!
katqanna
Well-known member
Regardless of any boundaries or surveys, they have not addressed the Unlawful Inclosure of Public Lands and a five wire fencing obstructing wildlife.
Yep and there are folks here who cautioned against relying on GPS for that purpose.Yikes fowladdict I don't want to think about that in light of corner crossing threads.
And that's assuming they are both projected in the same datum. Lots of small errors can add up to lots...
From earlier in the thread...
While I think these guys are douche bags, I does not surprise me at all that the fences were surveyed in. They didn't get their money by tripping over small details like that. They are making a point and making that point with the fence on their land where no one can do much is more effective.
While I think these guys are douche bags, I does not surprise me at all that the fences were surveyed in. They didn't get their money by tripping over small details like that. They are making a point and making that point with the fence on their land where no one can do much is more effective.
onX Hunt
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Interesting. According to Wingmans GPS the fence was almost 100 yards off from the boundary the GPS showed. Fowladdict said he has seen up to 100 feet off on his comparisons so 30 yards is his worst case vs. the 100 yards wingman saw. Ton's of surveyors and real estate agents use the map on a GPS all the time to find property pins and boundaries and we have never heard any concerns with accuracy over what Garmin GPS units claim which is 10-20 feet.
I don't think recreational GPS units are that far off. If so I should be living 3 houses down in my neighborhood. A 100 yards off would put me 3 lots over!
Matt
I don't think recreational GPS units are that far off. If so I should be living 3 houses down in my neighborhood. A 100 yards off would put me 3 lots over!
Matt
Nobody's doubting the garmin accuracy claims, we're talking about the GIS source data you're using.
Comparing house lot cadastral accuracy to giant ranch data in Eastern MT is ridiculous.
A ton of original PLS stones across MT have never been recovered, and every time they are boundaries move. Who knows how that boundary was drawn in by the GIS tech, and how accurate it is.
Don't think I'm trying to defend the Wilks in any way, just pointing out what I know. I've worked in both GIS and Survey, and they are entirely different processes for entirely different applications. This is a survey matter, not a GIS one.
Nameless Range
Well-known member
I have been involved in the maintenance/creation of data in Montana's Cadastral Dataset. If I had to lay money on it, I would guess the error is inherent in the data, and is not from the GPS unit.
Generally, parcels from newer surveys will be more accurate because they will have some GPS data incorporated into the survey, which improves its accuracy when it comes to including it into the cadastral dataset. For example, when parcels are split or subdivided by surveys nowadays, a D.O.R. cartographer reviews them and incorporates them into the cadastral dataset. Older surveys - who knows? They may have digitized from some old plats or something else entirely.
That said, because it is so difficult to verify stuff like this, I wouldn't put it past the Wilks that they could be in error. Who really goes to the Clerk and Recorder, copies the survey that created their parcels, and then reviews them with ground comparison? The truth is most people just use Montana Cadastral, which generally, is pretty good.
Generally, parcels from newer surveys will be more accurate because they will have some GPS data incorporated into the survey, which improves its accuracy when it comes to including it into the cadastral dataset. For example, when parcels are split or subdivided by surveys nowadays, a D.O.R. cartographer reviews them and incorporates them into the cadastral dataset. Older surveys - who knows? They may have digitized from some old plats or something else entirely.
That said, because it is so difficult to verify stuff like this, I wouldn't put it past the Wilks that they could be in error. Who really goes to the Clerk and Recorder, copies the survey that created their parcels, and then reviews them with ground comparison? The truth is most people just use Montana Cadastral, which generally, is pretty good.
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onX Hunt
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Good insight, that makes some sense now. I will do some surveying myself of the area in 3 weeks! I'm sure we will have more info and pictures to share!
Cheers,
Matt
Cheers,
Matt
fowladdict
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I will do my best to explain. While elk hunting two weekends ago, I saved my truck as a waypoint on my Garmin. At of curiousity when returning to my truck, I stood in the same place where I stored the waypoint and it told me to go 14-ft. So I buy the 10-20 foot accuracy Garmin states. Keep in mind that the accuracy is related to where you are in the real world Lat and Long wise. The GIS data that is used for property boundaries, section lines, and other landmarks CAN be within reason, but often is nothing more than an approximation. Garmin does not claim the accuracy of the data installed by mapping programs. I do sometimes use our data collector as a handheld when looking for section corners in relatively unsurveyed areas, but never more than a tool to get me close. With enough experience you will find that you lose accuracy in the GIS data that is input on those handhelds the further you venture away from developments. Unless the GIS data is based on a survey that is newer than original GLO surveys it can be hit or miss. Attached is a small example of what you can expect to see in the world of GIS.
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Rat Fink
Member
Aerials NEVER line up with cadastral data. Your pic is very misleading.
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