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Thread: Workflow suggestions regarding projections?

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    Alright, that sounds doable. And yeah, I will need to look what other tools I can find. From work I am most used to work with illustrator/photoshop, but they were not really meant for this kind of task I figure ^^ For now I will concentrate on the continent contours.

    I looked at your tutorial and found it quite useful. At first I reproduced the first steps using the vector data from natural earth, loading the file and then re-projecting it to some other projections as a test and it worked great. When I tried the same with a raster map however, I ran into some problems. I am not sure if QGIS is buggy though or if I made a mistake somewhere. While I could re-project the raster maps (down loaded some from NE) and the re-projection itself seems correct, it cuts of slices from the sides of the map. Projecting the original file to Mercator WGS 84 (EPSG:3395) for example cuts off a signignificant part of the top and bottom part of the map. I know mercator projections can't show the poles, however I am losing half of Norway too (everything north of Trondheim or so) which seems a little much. Other projections cut of the sides, so I am a little clueless what is going wrong.

    The .tfw and .prj files are named the same name as the raster map and sit in the same folder too. Is there anything else I need to change to reproject raster maps? In photoshop I would suspect I am trying to draw beyond the canvas borders, but if QGIS has such a setting I was unable to find it so far.

  2. #2
    Software Dev/Rep Hai-Etlik's Avatar
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    I just tried the same thing and it looks like a problem with On the Fly Reprojection. If you set the project CRS and enable On The Fly, all the layers will be projected into the project CRS Live, but this is computationally intensive, and not as reliable, particularly for Raster data. Try Raster -> Projections -> Warp. That will let you project the image to a new file.

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