How to choose the EPSG projection?


Up until now for reprojection of my WGS84 vector (.shp) and raster files (.tif), I have been using EPSG projections based on vector/raster central point’s UTM zone.

But what happens if the envelope-area of the vector or raster file spans through two UTM zones?
Here is an example of a raster spanning through UTM zones 40 and 41:

enter image description here

In that case is it even possible to use some EPSG projection or not?
Should one of the two UTM zones be picked?

Finding the origin in .laz file with LAStools


I obtained a .laz file, which I used lasinfo and las2txt to view the records.

 Scale Factor X Y Z:          0.00100000000000 0.00100000000000 0.00100000000000
  Offset X Y Z:                22717.000 31027.000 21.000
  Min X Y Z:                   23776.000 30560.000 14.859
  Max X Y Z:                   23807.997 30591.999 43.696
  Spatial Reference:           
PROJCS["SVY21 / Singapore TM",
    GEOGCS["WGS84, WGS84",
        DATUM["unknown",
            SPHEROID["unnamed",6378137,298.257223563]],
        PRIMEM["Greenwich",0],
        UNIT["degree",0.0174532925199433]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",1.366666666666667],
    PARAMETER["central_meridian",103.8333333333333],
    PARAMETER["scale_factor",1],
    PARAMETER["false_easting",28001.642],
    PARAMETER["false_northing",38744.572],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]]]

and a sample record is 23776.000,30560.047,19.450.

Now, how do I interpret the above information, as in where is the origin in which the record referenced? When I punch in the lat, long from the above, I got the point below. If that is the origin and the X and Y is pointing eastwards and northwards respectively, then my assumption is incorrect, as I am certain that the data originated from somewhere southwest of that marker.

enter image description here.

Extract longitude and latitude WGS84 EPSG:4326 from UTM coordinates [closed]


I made a template with different information about specifics locations, my main problem is that all the data I have created have to be transform into WGS84 EPSG:4326. Because the program I am using doesn’t “understand” the coordinates of my file. In summarize I want to know if there some way to easy transform the status UTM coordinates into WGS84 EPSG:4326.

Area units for output polygon in WGS 84 UTM Zone 32N using QGIS


I am calculating the area of my polygon and I have used WGS 84 UTM zone 32N to calculate the area (using geometry on the field calculator) of my polygon, and I obtained 745461 (without units).

How do I determine whether it is in square metres or square kilometres?

Does ETRS89 and UTM use the same zone (longitude and latitude)?


I’m building an app for the european country Denmark exclusively and I need to retrieve some geospatial data from a (geo)server.
I’m currently trying to determine wether UTM and ETRS89 uses the same zone (lng, lat) or if it varies in regards to Denmark especially?

An example for a UTM Zone for Denmark would be: 32U

Converting UTM to Lat Long inside a Game Engine(Untiy 3d)


This is my first post on Stack Exchange.

I have exhausted my research through the game engine forums, so I am trying this forum since you guys seem to be the experts.

I have an external device that is feeding in UTM grid coordinates into the computer and using Unity 3d Game Engine: www.unity3d.com. This is a VR type project.

Im using C# and Javascript, those are the two accepted languages in Unity. I have found this code for C# online and have tried working it to my project but there seems to be some conversion into the engine errors that im struggling with. Here is the code I found, is this something I can use or will it not work in this context?

Basically I want to plug in my UTM coordinates and spit out Lat/ Long.

Hopefully it is that simple to setup and I have provided enough information about my project.

 public class NewBehaviourScript : MonoBehaviour {
     public double utmEast; //The updated UTM Easting
     public double utmNorth; //The updated UTM Northing
     public string utmZone; // The updated UTM Zone user is currently in. 

     public static void ToLatLon(double utmX, double utmY, string utmZone, out double latitude, out double longitude)
     {
     bool isNorthHemisphere = utmZone.Last() >= 'N';

         var diflat = -0.00066286966871111111111111111111111111;
         var diflon = -0.0003868060578;

         var zone = int.Parse(utmZone.Remove(utmZone.Length - 1));
         var c_sa = 6378137.000000;
         var c_sb = 6356752.314245;
         var e2 = Math.Pow((Math.Pow(c_sa, 2) - Math.Pow(c_sb, 2)), 0.5) / c_sb;
         var e2cuadrada = Math.Pow(e2, 2);
         var c = Math.Pow(c_sa, 2) / c_sb;
         var x = utmX - 500000;
         var y = isNorthHemisphere ? utmY : utmY - 10000000;   
         var s = ((zone * 6.0) - 183.0);
         var lat = y / (c_sa * 0.9996);
         var v = (c / Math.Pow(1 + (e2cuadrada * Math.Pow(Math.Cos(lat), 2)), 0.5)) * 0.9996;
         var a = x / v;
         var a1 = Math.Sin(2 * lat);
         var a2 = a1 * Math.Pow((Math.Cos(lat)), 2);
         var j2 = lat + (a1 / 2.0);
         var j4 = ((3 * j2) + a2) / 4.0;
         var j6 = ((5 * j4) + Math.Pow(a2 * (Math.Cos(lat)), 2)) / 3.0;
         var alfa = (3.0 / 4.0) * e2cuadrada;
         var beta = (5.0 / 3.0) * Math.Pow(alfa, 2);
         var gama = (35.0 / 27.0) * Math.Pow(alfa, 3);
         var bm = 0.9996 * c * (lat - alfa * j2 + beta * j4 - gama * j6);
         var b = (y - bm) / v;
         var epsi = ((e2cuadrada * Math.Pow(a, 2)) / 2.0) * Math.Pow((Math.Cos(lat)), 2);
         var eps = a * (1 - (epsi / 3.0));
         var nab = (b * (1 - epsi)) + lat;
         var senoheps = (Math.Exp(eps) - Math.Exp(-eps)) / 2.0;
         var delt = Math.Atan(senoheps / (Math.Cos(nab)));
         var tao = Math.Atan(Math.Cos(delt) * Math.Tan(nab));

         longitude = ((delt * (180.0 / Math.PI)) + s) + diflon;
         latitude = ((lat + (1 + e2cuadrada * Math.Pow(Math.Cos(lat), 2) - (3.0 / 2.0) * e2cuadrada * Math.Sin(lat) * Math.Cos(lat) * (tao - lat)) * (tao - lat)) * (180.0 / Math.PI)) + diflat;

         print(latitude);// Looking to display in the Console Log Lat.
         print(longitude);// Looking to display in the Console Log Long.
     }
 }

Converting entire map to UTM 18 if only interested in part that is in UTM 18?


I am using some polygons and rasters whose initial extents cover all of Canada or all of North America. I am interested in a small area in Ontario that is in UTM zone 18. I would like to use the UTM 18 projection for this project. If I convert all of my layers into WGS84 UTM 18 using ArcGIS, obviously the parts of the layers outside of the UTM 18 zone will be horribly distorted. I will be cropping the layers after to only my zone of interest once they are all in the same projection. But will the part of the map that is actually in UTM zone 18 be distorted as a result of the reprojection of the entire span of Canada, or will this part be fine?

How to format the labels of a UTM Grid in a map Layout/Print Composer


I am doing a map in for a small area (1.5km by 1.5km on UTM zone 14N). I want to know if it is possible (and how to do it) to format the labels of a UTM grid. This is exactly what I want to show

a) On the Southwest corner of the map I want to see the full value of the coordinates (north or east). I want that the east coordinate shows the first 3 digits in a bigger font than the las 3 digits. For north coordinates I want the labels to show the first four digits in a bigger font than the remaining three digits. I also want them to show the suffix E or N accordingly

b) For the remaining east and north coordinates I just want to show the last 3 digits of the coordinate

I can use either QGis or ArcMap.

I tried to use ArcMap’s grid styles, particularly the USN National Grid and I have no luck. I also tried to use corner style labels feature no luck also

Difference between UTM 10U and UTM 10N? [closed]


I there a difference between UTM 10U and UTM 10N?

ArcGIS has 10N, but my scan map has 10U?

When I attempt to georeference, my scan gets skewed

Can I use Redfearn's formula to convert between WGS84 and UTM?


I have GPS data at 1 point per second for several weeks in WGS84 latitude/longitude form. It was collected using a UBLOX GPS in 2015 in Australia (Zone 55s)

Would it be correct to use Redfearn’s formula to project WGS84 data to Northings/Eastings? Normally it seems that Redfearn’s formula is used with GDA94 rather than with WGS84:

I would like to get Northings/Eastings in meters. The data is only accurate to 2-5m at the moment, but I don’t want to make it worse so would need to use a conversion that is accurate to within a few cm.

I could just use the ArcMap (ArcPy) projection but since I have very large files (1 point per second) even ArcPy is very slow. Therefore I’d rather put the formula directly into Python. I’ll probably use ArcPy later to check some of the results.

The data is collected on animal collars (in Zone 55s). The collars could be used anywhere in Australia (or possibly overseas) so I’d like to use a formula that could be transferable to another part of Australia (although that could involve user input about approximate location).

I’ve also been investigating how to convert WGS84 (presumably = ITRF2008?) into GDA94 and then to MGA, but this seems very complicated and I think it may be simpler just to work in WGS84 UTM since I don’t really need it for an official map.

Question and Answer is proudly powered by WordPress.
Theme "The Fundamentals of Graphic Design" by Arjuna
Icons by FamFamFam