Order of the coordinates' import

Is there a particular order for the to enter coordinates? Eastings before northing or northing before easting. I have a similar problem as being addressed here. I have coordinates in EPSG 2004. I uploaded them into a job set to EPSG 2004 but they do not plot correctly on the map displayed on the phone. The same coordinates when imported in QGIS plot correctly on top of the aerial photo for the area. I was able to do a coordinate capture in for the point I used as the base station. The fix obtained for the base station was comparable to what was obtained in QGIS. When the points were surveyed they plotted in the correct location on the map but significantly different coordinate values in as much as 300m.

What could be the issue here>

George

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Hi George,

Welcome to the community forum!

In ReachView 3, the columns in the imported file can be placed in any order.

May I ask you to share the CSV file with these coordinates so I could check it? You can send it to support@emlid.com.

Please also specify how did you collect these coordinates.

Hi George,

I’ve received the files from you. I’ll check them and will get back to you with the news.

We’re handling this over email as some of the details contain sensitive information.

I just did some observations on Sunday last using the local CRS. the base was on a point of known coordinates in both geographic and local coordinate system. The resulst given for the observed points in the local coordinte system is > 200m in northing and > 300m in the easting whe ncompared to previously done surveys. I also note the results given for the base station is of similar magnitude. Please the explain why the base station coordinates differ so greatly when the known wgs 84 coords were entered for the base setup in reach view.

Hi George,

Sorry for keeping you uninformed this long!

The shift of the collected points shown in ReachView 3 and QGIS lies in different ways of displaying them on the corresponding maps. The map engine in ReachView 3 expects the coordinates in Web Mercator System. That is basically WGS 84. Usually, the difference between the local datum and WGS 84 is small.

However, the Montserrat_1958 datum shifts from WGS 84 in 174 meters along axis x, 359 meters along axis y, and 365 meters along z. In this case, you can easily see the difference on the map as the coordinates are shifted more than 300 meters away.

The most suitable workflow for your local datum might be the site calibration with the other app. You may configure Reach to output the position via TCP to the QGIS app, for example.

I’m not sure I totally understand the full picture here. Could you please specify what shift has you mentioned and where do you inspect it?