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I am using QGIS 3.22 for LiDAR analysis, and I have a question about combining rasters. Pretty often, I have to combine several visualization methods to get a clearer result : for example, derive a Slope raster and a Sky-view factor raster of my DTM, and then combine them by putting the SVF raster on top of the slope raster and then select "Blending mode : Multiply" in the rendering properties of the SVF raster.

My question is, therefore : is there a way to make this type of blending permanent, by blending my two rasters into a single one ?

As there are a lot of option for LiDAR-derived raster rendering (hillshade, Openness, Local relief model...), I sometimes have quite a few rasters on top of one another, with different blending parameters, to reach the perfect visualization. It would make my life much simpler if I could replace my groups of rasters by a single raster - and for instance, it would help me to share them with colleagues.

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One way to do it is to export your desired visualization as an image

(Project/import/export/Export map to image). enter image description here

Just make sure of the following

a) calculate the extentent. If you want the whole raster, choose calculate from layer. If you want a section only you can use Draw on canvas.

b) Resolution. Play with this parameter. If the region is big and the base rasters have a high spatial resolution (0.5 m, for instance) could make qgis to not be able to export the image. So try some dpi that make your final image clear.

c) Choose Append georeference information if you want to use it later in a GIS.

Decorations and anotations are not mandatory if you want tou use the final image in a GIS

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  • Yes it does help a lot, that is exactly what I was looking for ! And with this I can adjust to one specific zone. It is perfect, many thanks !
    – Onesimos
    Sep 30, 2022 at 6:30
  • As per the help center please do not include chit chat like your signature within your posts.
    – PolyGeo
    Sep 30, 2022 at 19:49

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