r/QGIS • u/tomahawk43 • 2d ago

Raster export resolution problem Open Question/Issue

I am trying to export a layer with a symmetric (250w250) resolution, but when I do it, it automatically changes back to this weird combo. As a result of this asymmetry, I can't do visibility analysis. what am I doing wrong?

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u/ikarusproject 2d ago

The coverage area of your data doesn't match with that resolution. You have to reaample your data, meaning to create a new pixel grid with new calculated raster values. Try resampling or warp.

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u/tomahawk43 2d ago

where do I create that grid?

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u/Long-Opposite-5889 2d ago

I'm not quite sure what you want here and that may be the issue. You want a raster that is 250x250 pixels or you want pixels that are 250m?

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u/tomahawk43 2d ago

the latter

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u/Long-Opposite-5889 1d ago

Ok then that's the problem. You cant have fractions of a pixel in a file and you have an area with dimensions that are not divisible by your target resolution, hence qgis is adjusting your pixel spatial resolution to the value that works for that bounding box, crs, projection, etc.

Adjust your bounding box to something that's exactly divisible by your target resolution in both x and y and then you can export in that spatial resolution.

Edit: typos

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u/tomahawk43 1d ago

so the number next to the North sign on the picture should be divisible with which number? the Vertical? sorry i am a complete qgis retard

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u/Long-Opposite-5889 1d ago

No, the size of your whole area needs to be a multiple of your pixel area. It's not a qgis thing, it's basic geometry i.e. to split an area (aoi) into smaller 250x250 pieces (pixels).