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Grid vs Ground Coordinates

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Norman_Oklahoma
(@norman-oklahoma)
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I agree with John that we may assume that any metadata we offer in our submissions will be jettisoned by the time final plans are generated.

And while I see his point about scaling about 0,0 and truncating I also understand why people scale about a point central to the project and don't truncate. Doing so leaves a survey that will fit to GIS planning level stuff that designers rely on so heavily while having true ground distances - as long as the project area is contained within a few square miles. Which is most of them. It's a PITA, but that is just our cross to bear. Low Distortion Projections address this scaling problem very nicely.


 
Posted : September 25, 2024 5:43 am
dmyhill
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...I also understand why people scale about a point central to the project and don’t truncate. Doing so leaves a survey that will fit to GIS planning level stuff that designers rely on so heavily while having true ground distances – as long as the project area is contained within a few square miles. Which is most of them. Low Distortion Projections address this scaling problem very nicely.

This is the easiest way to make the GIS people happy.


 
Posted : September 25, 2024 9:14 am
OleManRiver
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Yes I agree. It should not matter if you scale about 0,0 or a point on site and if you truncate. GIS people should if given the location scale and all other information should be able to build that mini datum right back to nad83 state plane easy enough. Most GIS people I deal with the ones who come to survey conferences and such understand that the LDP is gold but that requires their techs to have the information to build that in and suck it in.


 
Posted : September 25, 2024 9:23 am
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