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I have about 800 geoTIFF files that have an unspecified projection, but since I know the projection (WGS 84 UTM Zone 32N), I have used the “define projection” function to batch define the projections of these files. Now I need to clip all of these files to a new extent using a shapefile with the same projection. However, when I checked the files I saw that they do not overlap. My shapefile shows up all the way at the top of the screen and the geoTIFFs are tiny dots in the middle of the screen. Actually, they are so tiny that I can’t see them in global view, but I know that they are there. The data has almost the same extent, so they should be the same size.

The spatial reference data and extent data is shown below for each file type. The difference I see is in the extents, but I don’t know how to fix this problem, or even if this is the source of my problem at all. Does anyone know what might be wrong and how to make my files overlap?

geoTIFF file 
Spatial reference 
XY Coordinate System
WGS_1984_UTM_Zone_32N 
Linear Unit Meter (1.000000) 
Angular Unit Degree (0.0174532925199433) 
False_Easting 500000 
False_Northing 0 
Central Meridian 9 
Scale_Factor 0.9996 
Latitutde of Origin 0 
Datum D_WGS_1984

Extent Top 6720.20271636 
Left 370.036258324 
Right 461.540519838 
Bottom 6651.1691216


Shapefile 
WGS_1984_UTM_Zone_32N 
WKID: 32632 
Authority: EPSG
Projection: Transverse_Mercator 
False_Easting: 500000.0
False_Northing: 0.0 
Central_Meridian: 9.0 
Scale_Factor: 0.9996
Latitude_Of_Origin: 0.0 
Linear Unit: Meter (1.0)

Geographic Coordinate System: 
GCS_WGS_1984 
Angular Unit: Degree (0.0174532925199433) 
Prime Meridian: Greenwich (0.0) 
Datum: D_WGS_1984
Spheroid: WGS_1984
    Semimajor Axis: 6378137.0
    Semiminor Axis: 6356752.314245179
    Inverse Flattening: 298.257223563

Extent 
Top 6733114.02831481 
Left 364349.954284994 
Right 501090.000365895 
Bottom 6620131.02208354
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  • 3
    Are you sure that geotiff's are in the right coordinate reference system? If it is, they have an extent of ~69 m x 91 m... Seems that projection is wrongly defined
    – aldo_tapia
    Oct 24, 2017 at 12:27
  • All I have done to the original tiffs is batch "define projection" to the coordinate system WGS_1984_UTM_Zone_32N. The information in the text above is directly from Arc Catalog, so I think it is correct?
    – Tessa
    Oct 24, 2017 at 12:30
  • 2
    Yes, but you know the data... Are the extent of your rasters consistent with the data? Seems to be too small. For orthophotos could be ok. In the other hand, your shapefile has an extent of ~100,000 m x 136,000 m, completely different of your rasters extents. For this difference, I think that WGS_1984_UTM_Zone_32N doesn't represent your data
    – aldo_tapia
    Oct 24, 2017 at 12:37
  • 3
    There are a lot of "extents don't match" posts here, and nearly every one maps back to a "your projection isn't what you thought it was" answer. We don't have your data, so we can't do any sleuthing, but you need to entertain the possibility that at least one of your datasets is in the wrong coordinate reference. Note that there are an infinite number of UTM 32N projections due to false origin variance.
    – Vince
    Oct 24, 2017 at 12:43
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    Ah! I think the geotiffs are in kilometers. You're going to have make a custom UTM 32N using kilometers (make sure the false easting value gets converted to 500.0) or regeoreference the tiffs to meters. Maybe there's a raster calculator function that could do that...?
    – mkennedy
    Oct 24, 2017 at 17:22

1 Answer 1

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I managed to fix the problem. The GeoTIFFs were in kilometers. I only had to multiply the extent by 1000 and the tiffs overlapped perfectly with the shapefile. I did this in R using the extent function that is part of the raster package. Code below:

bb <- extent(370036.3, 461540.5, 6651169, 6720203)

extent(dataset) <- bb

dataset <- setExtent(dataset, bb, keepres=TRUE)

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