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Clark 1866 ellipsoid

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(@olemanriver)
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@jacavell well things are changing but most people are never in wgs84 for survey grade no matter what they say historically. I remember hearing well close enough in past.  Yes tbc is. Great tool i love it but like any commercial software some things were not accounted for. If i were not such a checker i would have accepted the nad 83 2011 to nad 27 and it wouhave worked on the ground relatively well. But when my boss said we are contracted to be on nad 27 i did the ncat checks. Always have before ncat nadcon corpscon vertcon etc. I like to always go back to whoever is the caretaker of the datum to do a check.  Especially since i am relatively new back in private sector.  I learned a lot working at NGA and Lso dealing with vendors. And checking the list twice like Santa clause is a must.

 
Posted : 18/03/2023 10:15 am
(@olemanriver)
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@dougie surely surveyors will not be bad word. This stuff will they.

 
Posted : 18/03/2023 10:20 am
(@olemanriver)
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I can’t use with today’s tools data collector and software and office software why its so frowned upon to use a robot or other total station and just work on grid. Even if on grid one can easily produce acreage and ground distances for plats etc.  we still have a mindset that gps is grid and robot is ground and mixing is bad so we make some hybrid system that works between the two and then we give that information to a county and raise a stink that gis folks are rubber sheeting. If we gave them true datum coordinates and the metadata the. We could extract that back for future use.  I am not a pro just coordinate surveyor either. Trying to figure out whether a plat that has a north arrow stating grid north datum x spc.   Xxx. Is ground distance or grid distance when no other piece of information is available is not wise.  I re traced one recently that had placed coordinates on some of the corners. Evidently they were scaled after I surveyed the parcel as my bearings matched within reasonable amount and my computed ground distances matched between monuments. The coordinates out of the gate were feet off. Not from themselves but known datum. As i had checked into ngs monuments and published control on airport all within the size of a dime.  No where on the plat was a scale factor used and where from.  I did some reverse engineering and probably had a good guess it was a one point cf for entire survey. Location had been given with cf that was used i could have computed exactly where the corner was and saved a little time. So i just field computed by bearing and distance as I checked as i surveyed. I stayed in grid used the ground distance and grid bearings and followed very closely. All the pipes were found I needed for what i was doing.  Truthfully I didn’t need any coordinates but if you are going to give them the. Give them correctly please. Lol. 

 
Posted : 18/03/2023 10:40 am
(@jacavell)
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@olemanriver 

Seems to me you are doing what you can to interpret what others have done and how to make it not so hard for those who follow in your footsteps.

 
Posted : 18/03/2023 11:47 am
(@jacavell)
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@olemanriver 

Licensed surveyors are usually at the end of the line when after something goes wrong and the finger-pointing begins. There is no one else to point at.

When we realize the value we bring to projects and charge for that instead of for hours like laborers.

There is a cute aphorism that goes something like

“You don’t pay me for the 5 minutes I spent to do it, you have to pay me for the 10 years I spent learning how to do it in 5 minutes”

Besides "getting it right" we are liable to defend ourselves against even imagines torts.

Everyone likes to criticize the surveyor but they need him to be there to take the blame.

 
Posted : 18/03/2023 11:57 am
(@olemanriver)
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@jacavell so true.  I am working towards that goal. I probably should have been already licensed years ago. But after 7 plus years in private sector I joined the USMC became a geodetic surveyor and studied and produced cartography and remote sensing and multi etc gis and such. When i got out I wanted to find a good surveyor to be mentored by and get back in the game. So I started by being a trainer for Trimble dealer to learn who was who. But life is life and I ended up building a vrs network and teaching many surveyors the pros n cons of rtk gps grid vs ground etc and personal things happened about the time the economy crashed so I went to work as an orbital analyst and worked my way up to a title of orbital scientist. Which is just a title.  I learned a lot but still am no where near i would like to be. Few years back the wife asked why i just didn’t go back to land surveying and run my farm. I was tired of the suit and tie and 24/7 shift of the gps constellation and had come to a point that I realized i just flat out missed boundary surveying. So i made a few phone calls. Base9 helped point me to a surveyor who i worked part time for and got my feet back under me. Set for the first national exam last year and getting ready for the next one and state specific one. I have a lot to learn but land surveyors do as well.  I am now trying to get my drafting skills up and its a chore. And of course learning all commercial software again is totally different than software that federal agencies run. I am loving being back but get frustrated when my geodetic brain hits the Land Surveying wall of this is how we do this. When using gnss and datums. The whole projected coordinates thing blows me a way how so much of this is what and how we do this.  I am like its so much easier to do it correctly than the hybrid lazy way in my opinion. Maybe its just that pressure of getting in and out to turn a dollar than to sit down and actually understand how the equipment and software can do so much more. Can you imagine if the inverse forward and backward was not 180 and the sum of interior angles did not equal n-2x180 because we had to use geodetic azimuth vs grid etc.  heads would explode lol. I showed this to a up and coming young buck and he was like what. I said we work on the Land Surveying side as the interior angles of a triangle equals 180 but not in the geodetic world. He is studying for his fs now. And a sample problem was kicking him on the azimuths not matching forward and backwards. Well i am done feeding cows and checking calves. So off to shower and get ready for a dinner with the family. Always fun on this site so many knowledgeable people and we are all learning together.

 
Posted : 18/03/2023 12:20 pm
(@olemanriver)
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@jacavell i try. I have one of those brains that doesn’t function well just being gold do this plus this and we are good. I have to dive in and understand so i can learn.  I beat the drum every time i see the standard operating procedure of choose a point in middle of site and scale to ground.  Finally had a job that i was able to use to show why that doesn’t always work and why it should always be checked when applying that. Still have distortion and sometimes more than leaving it at grid. Long linear project lots of elevation change up and over a mountain.   They sent a point off to opus used that factor. Ran traverse on scale 1.000000. About as far away from central meridian and the two parrLlels. Running in a direction the scale itself changed at every turn and then the height change. I said this is not going to work. Oh yes we do it all the time.  Lol. You know what happened next. Angles didn’t close nor distance. To opus observation on the other end of over a mile. I said if you didn’t scale and left it all at grid you would be fine and then figure out a project scale that would work for the tolerances needed along the surface. Nope push this button do this we are done. I just grinned and said ok. Guess who had to fix that mess. I put it all at grid and re computed all the traverse data along the route to grid and a decent closure but i didn’t know how to do it in tbc at the time so old school it was.

 
Posted : 18/03/2023 12:32 pm
(@olemanriver)
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@jacavell that statement “Following in the Footsteps “ has been beat into my brains since I first started surveying. I cherish that statement for sure. However, I think some have been saying it that they fail to see it’s meaning. Because the only way we can follow is to know and the only way we can be followed is to leave tracks that are not covered up or lead someone down the wrong trail.  I kinda think that when metadata is not complete its just like taking a branch and scrubbing out the tracks we are to leave.   I have no idea if i will ever do this but at one time as i was off during war time doing geodetic work my mind had wondered and i was thinking about the boundary surveys where a snake or wildlife was my only threat.  Anyway i said with my knowledge i have learned here in this geodetic world and combined with Land Surveying maybe i will have a plat one day that has everything on it. So in a lambert the most northerly and southerly ends and possibly in the middle have the latitude drawn in kinda greyed out with the scale. Then also on a few longest lines show the geodetic north at te same line off to scale along with grid bearings etc. but i have to learn to draft basic stuff first lol.

 
Posted : 18/03/2023 1:13 pm
(@dougie)
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@olemanriver


GIF
 
Posted : 19/03/2023 4:18 am
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