Ha! And nobody is bending each stick of pipe to conform to the curvature of the earth. ; )
Trying to get more familiar with the language here and surveying coordinate systems in general. Starting to piece through this which I found very informative for what we are discussing. I’ll have more to add as I digest this.
http://www.ejsurveying.com/uploads/2/5/6/6/25668328/working_with_grid_coord.pdf
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If there was an inverse scale factor applied to the Emlid data would this have been closer? Or maybe it was done and still off? Inverse meaning not from ground to grid but grid back to ground.
@RTK_Hunter, You are totally correct in the sense of your example, but this is another instance where localization eats up the majority of the error. Very rarely do we have a site (road job) longer than 5 miles. Most of them are around 2-3 miles so it hasn’t been and issue. We always try to setup the base at the midpoint of a job so even 7 or 8 miles wouldn’t show much error. On top of that we shoot all tie-ins independent of the drone so we can adjust the last 50-100ft and needed.
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I’m not clear on this? If I understand at all I think you are talking about the grid scale factor. We typically see that 1.00012xxx is applied for the plans so we will have to apply 0.99998xxx to get the drone data back. This is a horizontal only scaling. The testing was done before I was trying to use Magnet with the Reach so it was Topcon w/ Magnet and Reach RS+ with Reachview.
We have EUREF89 NTM grid coordinates for this kind of job. This is used when UTM doesnt cut it.
NTM has 11ppm vs UTM with 400ppm. NTM works well on large area project.
For the pipeline situation (e.g 1000km), one really need to do a thorough survey to get the correct distance.
Plain A-B with some advanced spheric model doesnt do it well. At least not in my area where hills go up and down faster the you can say Survey 
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Yes, I wasn’t sure if the Emlid data needed to be adjusted with a grid scale factor to translate into to ground plane coordinates.
Sometimes. It is inconsistent as the whether or not the CAD files have a scale factor applied. Some Engineers are really good about it and others you get what you get. Likewise as to whether or not that fact is in the plans for construction. It’s a fun game we play.
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Hi everyone,
It’s been a long time since the last reply here! But I wanted to add my two cents, answering the question that started this topic.
Now we have the ReachView 3 app, which supports various coordinate systems and vertical datums, including State Plane CS and NAVD88. You can find more details about the possible setup in our guide for the USA. As for localization, it’s in our roadmap.
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