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I'm trying to export a TIF image from a satellite image (from plugin "QuickMapServices").

I tried several ways like :

  • Saving raster layer as GeoTIFF (the simple option ("export" from the drop-down menu of the layer)
  • The algorithm "Convert map to raster"
  • Export the map as .tif from the print composer (I changed the dpi from 300 to 1800, but it doesn't change anything).

As you can see on the image below, the current satellite image has a higher resolution than my exports. Even when I set the columns/rows resolution to 1.

Example

Do you think I could export data with the same resolution ?

EDIT:

Here are my setting when I export the image :

CRS : EPSG 3857 - WGS84 / Pseudo-Mercator Extent : I use a shapefile map extent Resolution Horizontal: 0.5 / Vertical: 0.5

There is still a difference in the result.

Image

1 Answer 1

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When using the export function, what settings do you use?

Can you try:

Format option: GeoTIFF  
CRS: Mercator  
Map Extent: Map Canvas Extent  
Resolution: 0.5 meter (depends a bit on the satellite source you're using)  
Image resolution unit: meter   

If another CRS is used you might have to convert the 0.5 meters into degrees.

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  • I edited my first post. Used 0.5m as suggested, but still a difference. So I'm trying 0.1, but it will probably take a while. I'll update late.
    – Giene
    Feb 17, 2023 at 10:31
  • In google earth for the same location it should be possible to find the source of the image, and from that find out the exact spatial resolution of dataset, to avoid over- or under-sampling.
    – Heigre
    Feb 17, 2023 at 10:47
  • Indeed, but if I do so, the result will not be georeferenced right ? Or is there another way ?
    – Giene
    Feb 17, 2023 at 13:17
  • It's been almost 3h I started to export my image with 0.1m resolution and only 15% are achieved. I'll wait, but it is probably not the best way.
    – Giene
    Feb 17, 2023 at 13:19
  • Using google earth would just be to find the correct spacial resolution to use in qgis. Hmm, 3h for the export definitively does not seem right. How large in gigabytes is the 0.5m dataset? I think I would try to kill the process and try to do a new export with say, 0.2m resolution, and then compare the export with the 0.5m export to see if it affects the image as intended.
    – Heigre
    Feb 17, 2023 at 14:51

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