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I am exporting very high-res (7000x7000px) hillshades from ArcMap as tiff files. I am then doing some work in photoshop to the images.

How can I easily georeference these tiffs after working on them in PS?

Is there a way I can simply define the coordinate system and the bounds of the tiff without using ArcMap?

I am trying to avoid ArcMap because I seem to loose all me edits from PS and ArcMap just has a tendency to foul things up once I reimport. I have QGIS installed if that might be a better approach.

  • have you any reference points in it. like, eg a road building etc that you see on the image? – Ger Feb 20 '14 at 21:42
  • I know the exact corners of my tiff in decimal degrees. I am trying to avoid any ruberstamping in ArcMap. – jotamon Feb 20 '14 at 21:43
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    Then just straight up georeference in qgis....pick points and entre co ords – Ger Feb 20 '14 at 21:44
  • Yes - go to properties of the edited tiff in ArcCatalog and assign the same Spatial Reference in the properties. However even without this process the tiff should appear in the correct location but displays a warning that Spatial Reference is missing. – Jakub Sisak GeoGraphics Feb 26 '14 at 15:03
  • Wonder if you could export or write a world file and save the file and then once when you are done in PS and then before you bring it back to ArcMap. Rename the world file and put that file back in with the TIFF file ? Would that work ? – PROBERT Feb 26 '14 at 16:03
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As you know the coordinates of your corner, and assuming you also know the pixel size, you can create a world file that can be interpreted by most software. you just need to create a small text file with the extension .tfw and the same name than your tiff file. See Wikipedia for details. Here is the content :

size X

rotation X (probably zero)

rotation Y (probably zero)

size Y (negative if you use upper left coordinates)

upper left X

upper left Y

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When you export the images from ArcGIS, check the Write World File check box. This will create a world file (*.TWF) with the same name as the output tiff. The world file stores the georeferencing information. Always keep the twf file with the tiff. IF you do not resize or crop the image in Photoshop, or change the data frame coordinate system, the tiff will be geoferenced.

  • I cannot check the write world file box when exporting from the layout view. I would prefer to export from layout instead of the data view – jotamon Mar 18 '14 at 22:44
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I use the tools listgeo and geotifcp. Before you start your work with photoshop retrieve, the geoinfo with listgeo and store it in a file. After your work in photoshop is finished put the information back with geotifcp file (..look also at also Geotiff).

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I tried to do what you have done and don't seem to have an issue:

  1. export hillshade to a new TIFF file.
  2. open the exported TIFF in Photoshop and edit the image
  3. save the file and close Photoshop
  4. Open TIFF in ArcMap - Wanrning displays that spatial reference is missing.
  5. Ignore wnarning - edited TIFF is displayed in ArcMap in the correct location
  6. Remove the edited TIFF from ArcMap
  7. Open ArcCatalog, locate the edited TIFF, go to properties, change the "Unknown" Spatial Reference to the correct Spatial Reference (Same as the original Hillshade raster)
  8. Add edited TIFF to ArcMap - no warnings are displayed

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