DonK

Plotting Historic Bearing Points

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I have a historic series of survey bearing points in the format: rods (distance), S. 55° E. (bearing). Is there a way to use ExpertGPS to convert these points to track points given the start coordinate? In the past, I have constructed a spreadsheet to do the conversion, but I'm looking for a simpler way which will also plot the resulting points on a map.

I have found a ten year old discussion on this topic of the forum, but nothing else.

Thanks,

Don

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Yes, mark your starting waypoint on the map, right-click it, and Project Point. You can plot each point in succession by entering the distance and bearing from your survey.

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Thanks, Dan, that works well. I even have the option of using rods as my measurement unit. I am plotting from a ca. 1805 survey of the Union Turnpike which ran just north of you from Concord to Leominster. I also add in the change in magnetic declination from 200 years ago. I'm not sure whether the EGPS default magnetic declination can be changed.

When I was looking at the cursor distance and bearing readout in the lower right-hand corner of the screen, I noticed what appears to be a clipping of part of the readout. I've included a screenshot. Is that a part of the bearing information?

post-3479-0-16687500-1452477592.jpg

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Don

Thanks for asking that question. Hadn't thought to use this to do that - with Civil 3d at hand.

But that then begs the question of how precise (decimal places) does this work. If you can go to the hundredth of a foot and second of a degree it could be an interesting tool for more than rough reconstruction..

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ExpertGPS doesn't limit or round the bearings and distances you enter. You can enter hundredths of a foot, and ExpertGPS will do the calculations using those values.

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