2

I have 2 shapefiles which you can find here.

I made neither of them they were both given to me. Their .prj files are:

One that projects correctly in both programs

PROJCS["NAD_1983_UTM_Zone_10N",GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",500000.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",-123.0],PARAMETER["Scale_Factor",0.9996],PARAMETER["Latitude_Of_Origin",0.0],UNIT["Meter",1.0]]

One that projects correctly only in Google Earth Pro

PROJCS["NAD_1983_UTM_Zone_10N",GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",1640416.666666667],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",-123.0],PARAMETER["Scale_Factor",0.9996],PARAMETER["Latitude_Of_Origin",0.0],UNIT["Foot_US",0.3048006096012192]]

they are supposed to overlap like so they are supposed to overlap like so

But in QGIS (2.8.9-Wien) they are far apart

  • Also see if WKID EPSG::4410 is supported. That's a USFoot UTM-based projcs. – mkennedy Jul 27 '17 at 23:14
  • @mkennedy but based on NAD27. EPSG:4430 is based on NAD83, Both are included in QGIS 2.18.11. – AndreJ Jul 28 '17 at 11:06
7

You have almost the same projection in both map. The difference between them is the CRS's unit. You need to create a custom CRS in Settings / Custom CRS using this proj4 setting:

+proj=utm +zone=10 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=us-ft +no_defs

enter image description here

After this, set new CRS in grid layer on properties window:

enter image description here

It should work:

enter image description here

2

The Datum are different, the top is in meters and the second in US ft (1 m = 3.2808333333465 ft) - Therefore the data should not sit exactly on top. ...it may also be due to the False Eastings which are both different, this will place the projection tangent (the point which the projection bisects the hemisphere) differently and cause a slight distortion. By converting the data to the same coordinate system with the same vertical units the data sits perfectly.

  • It's not the datum, but the units of the projection. As a side effect, the False Easting in the WKT definition is in the projection units, while in the PROJ.4 definition would be always in meters. – AndreJ Jul 28 '17 at 5:44

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.