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I have an ASCII Grid file + .prj file and can visualize this in qGIS. I can colorize it by going to properties and using a Pseudocolor Ramp. However, I want to export this now as a TIFF / Raster. Any ideas on how I can properly export this? Right clicking the layer, there is no "save-as" option :/

I assume I need to somehow apply the color ramp to the ascii grid first, instead of just visualizing the color ramp.

Thanks

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You can use gdaldem color-relief from the Raster menu to do this:

Raster -> Analysis -> DEM (Terrain models)

Change the Mode to 'Color relief'.

You'll need to make a text file that sets the rules for colouring the (asc) raster according to pixel value. See the section on color relief here: http://www.gdal.org/gdaldem.html for guidance.

This is still my preferred way of making elevation-coloured GeoTIFFs from DEMs, because of the control it provides (the input raster doesn't have to be a DEM, by the way).

You might also find this to be of interest: http://linfiniti.com/2010/12/a-workflow-for-creating-beautiful-relief-shaded-dems-using-gdal/

Using gdaldem from the command line makes it very easy to tweak the text file and do re-runs, until you get the result you want.

N.

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In QGIS 1.9 Master there is now a Save As button. You need to then select 'Rendered Image' as the output mode.

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