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I have 2 vector shapefiles of Manila that are supposed to align, but they do not (screenshot attached). I have projected them to the same projection (World Mercator WGS 84, EPSG 3395). One shapefile appears to be shifted to the right and does not align with the Google Street basemap and the other shapefile. I am using QGIS 2.14.16.

The pixelised shapefile in the picture was actually from a MODIS 500m raster image which I polygonised. The other shapefile is the administrative outline of Manila, from GADM.

I understand that MODIS data may have some misalignment issues that may be the cause of this problem, which I have not seen in other forums.

Any ideas as to what could be the problem and solution?

enter image description here

Tried to change the shapefiles to EPSG 3857 to match Google Street's projection as suggested by AndreJ. Unfortunately both shapefiles are more misaligned. enter image description here

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  • Google basemap should be EPSG:3875. 3395 might lead to wrong results. What was the original CRS of the shifted layer?
    – AndreJ
    Jul 3, 2017 at 5:52
  • Thanks for your input! Tried to change both shapefiles to EPSG 3875. Both shapefiles are now even more misaligned unfortunately. Will upload a screenshot to my original question.
    – adele.k
    Jul 3, 2017 at 6:00
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    If you did Set CRS for Layer, that was wrong. set the project CRS to EPSG:3875, and take the shapefiles with their original CRS. Can you link to the MODIS file download site? Does the raster align with the GADM shapefile?
    – AndreJ
    Jul 3, 2017 at 7:05
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    Maybe related: gis.stackexchange.com/questions/152663/… There might be something wrong in the conversion from MODIS to shapefile, regarding sphere vs ellipsoid.
    – AndreJ
    Jul 3, 2017 at 7:16
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    Note: 3857, not 3875.EPSG::3875 does exist---for use in Finland.
    – mkennedy
    Jul 3, 2017 at 18:21

1 Answer 1

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The alignment error must be somewhere in the preprocessing of the data.

You can find MODIS land cover data for Manila at ftp://ftp.glcf.umd.edu/glcf/Global_LNDCVR/UMD_TILES/Version_5.1/2012.01.01/MCD12Q1_V51_LC1.2012.PN5152/

and it fits quite good to an Openstreetmap background:

enter image description here

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