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I have data from a total station representing the various points on an archaeological site. The data is in an excel spreadsheet, and I have managed to import it into QGIS as a .CSV file. I also have the GPS location of the total station, and some more GPS points across the site.

My problem is the GPS points and total station points don't line up.

How do I geo-reference the data points?

The data I received in an excel spreadsheet format that looks like this:

1   298 8   20  298,1388889 5,203505239 15,023  -13,24738609    7,085004642
2   285 4   40  285,0777778 4,975545846 9,168   -8,852378721    2,384872111
3   220 3   30  220,0583333 3,840742463 12,823  -8,252462115    -9,814591078
4   180 43  40  180,7277778 3,154294772 14,754  -0,187402016    -14,75280978
5   181 20  40  181,3444444 3,165057636 12,891  -0,302459327    -12,88745124
6   159 47  10  159,7861111 2,788793738 12,457  4,30421347  -11,68976456
7   145 53  10  145,8861111 2,546192972 13,486  7,563484269 -11,16538856
8   156 4   45  156,0791667 2,724095352 15,37   6,232135259 -14,04981815

I have no idea which column is which - but I do have the total station location (gps point)(S32.60447 E20.88538)

I think the total station datum point was not set-up correctly (geo-referenced)?

  • Welcome to GIS SE! Are your GPS points and TS points of the same locations? In what way do they not line up? Can you please edit your question to give a bit more information about your data and the problem you have encountered? – Midavalo Jun 5 '17 at 19:16
  • Probably a projection setting, what format is the csv and gps coordinates? – Mapperz Jun 5 '17 at 19:17
  • How different are they? How good was the GPS device? Hand-held or professional grade? Did the GPS data undergo any RTK or post-processing? – mkennedy Jun 5 '17 at 20:27
  • You should ask the provider of your data to explain the data, and potentially to post-process it to the format you need. – BradHards Jun 6 '17 at 21:51
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I guess that the fifth column is the bearing, 7th the distance, 8th and 9th cartesian coordinates relative to the reference point. Columns 2 to 4 might be deg-min-sec of the bearing. Column 6 might be height-related.

So you have to put up a custom transverse mercator coordinate system on the GPS coordinates you have:

+proj=tmerc +lon_0=20.88538 +lat_0=-32.60447 +k=1 +x_0=0 +y_0=0 +datum=WGS84 +units=m +towgs84=0,0,0,0,0,0,0 +no_defs

assign it to your CSV and compare it to Google Satellite background via the QuickMapServices plugin.

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