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I have handwritten coordinates in the following format from a eTrex 10 device. Here are three of them.

E00197638 N00135887

E00197627 N00135939

E00197555 N00135964

They should be located in Sri Lanka, so I'm guessing the device was set up to show the UTM UPS Coordinates, he didn't write down the zone, so I'm further guessing the zone should be 44N. I have tried importing them just like that into QGIS by wriing them into a text-file (ID,x,y [Enter] 1,00197638,00135887) and using the WGS 84 datum, and UTM 44N (EPSG:32444) datum. However I arrive at random locations out of the earth or in the Indian Ocean. How can I transform these coordinates, and more importantly how can I identify the datum of those coordinates for the future.

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  • There is something odd with your coordinates. Using Google Earth, If they were UTM the will be in the range of 330,000-614,000 m E and for the north 627,000-1,118,000 m. Nor they are lat long 79°-83° lonE, 5-11°lat north. How did you configure the etrex coordinate display?. I am aware that this model includes a USB cable (I have the exact model). Can you download the data with a GPS application such as EasyGPS? Doing this will download the data in GPX format and in lat lon WGS84 that you can load in qgis, and reproject to UTM Aug 24, 2016 at 15:58
  • That's exactly my point. They are odd... unfortunately I just have the handwritten coordinates (literally on a piece of paper, exactly written down like this). Neither the device, nor the .gpx data.
    – Lukas
    Aug 24, 2016 at 16:02
  • Sorry, I think they are in some odd GPS CRS, I checked in my unit and I can not find any grid related to Sri Lanka. The closest is the Indian grid system but I am totally unfamiliar with it Aug 24, 2016 at 16:09

1 Answer 1

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I hope this may help you. I did some research on Sri Lanka coordinate systems at spatial reference. I found some crs that may apply to your problem. For testing purposes I used EPSG 5324 (Kandawala / Sri Lanka Grid) SR-ORG:7765 : +proj=tmerc +lat_0=7.000480277777775 +lon_0=80.77171111111112 +k=0.9999238418 +x_0=200000 +y_0=200000 +a=6377276.345 +b=6356075.41314024 +towgs84=-97.0,787.0,86.0,0.0,0.0,0.0,0.0 +units=m +no_defs

You will not find directly this CRS in Qgis. I defined as a custom CRS (Settings/Custom CRS). I loaded your points, declared that they were in my custom crs, reprojected to EPSG 4326 and your points lie now in Sri Lanka near Udawalawe National Park.

enter image description here

I made the image using the reprojected points and OSMMapnick from Quick map services plugin. If the location of the points is correct you can define the CRS I mention before, or look on some of the others here:

http://spatialreference.org/ref/?search=sri+lanka

hope it helps

Gerardo

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  • Holy...! Thank you very much! My friend is away until Saturday, then I can ask him if the points are correct. I do think that this might be correct, as it should be in the Udawalawa region. I will mark this as answered as soon as I know more!
    – Lukas
    Aug 25, 2016 at 15:40
  • Just one thing the points you see were reprojected from the Kandawala-Sri Lanka Grid to lat lon wgs 84 (EPSG 4326). Once you do the same with the other points, it will be easier to reprojetc them to UTM if you need it. Saludos from sunny Mexico Aug 25, 2016 at 16:29
  • When I'm looking at the device (which I have in my hand), the configuration of the coordinate system is the following: Position format: User Grid, Map Datum: Kandawala and Map Spheroid: Everest. This is by far the most ridiculous configuration I have ever seen. I think your solution is fine. Thank you very much!
    – Lukas
    Aug 27, 2016 at 9:47
  • Yes Indeed, but on the bright side you have the unit and play with your data in gpx format Aug 28, 2016 at 2:54

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