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I have created a GeoTIFF world map,

but I notice that it cannot be rendered correctly at zoom level which are low (e.g. zoom level 0, 1, 2).

enter image description here

Is it a predicted behavior or how can I fix this?

I also recorded a Youtube video for demonstration

Update： There is a screenshot the same GeoTIFF file mapping at zoom level 5 (scale 1：18524092). I think under this scale, it's mapping well.

enter image description here

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    There's no zoom levels in QGIS, there're scales. Which scale range are you talking about? Which CRS are you using? – Erik Jan 26 at 8:18
  • looks like a CRS mismatch – Ian Turton♦ Jan 26 at 8:38
  • @Erik thanks for reply. I use the plugin show the zoom level conversion at QGIS status bar , scale like 1:295829344(level 1.0) or 1:147914672(level 2.0), the CRS of tiff file is GWS84 (epsg 4326), QGIS canvas CRS I tried are WGS84 and Spherical Mercator (epsg 3857) – SCKU Jan 26 at 14:53
  • @IanTurton thanks for reply. I think QGIS will do the CRS on the fly transform automatically, and if I try to zoom in at high zoom level(scale zoom in over 1:147914672), the mapping result is pretty good. – SCKU Jan 26 at 14:57
  • QGis can only do the reprojection if the two layers are correctly projected to start with and I don't think they are. – Ian Turton♦ Jan 26 at 17:02
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This seems to be the bug described here or something similar. It affects raster layers when the bounding box is bigger than the raster layer. When you zoom in, everythin is perfect.

This behavior is common for my QGIS installations on different machines with EPSG:4326 as project CRS (not 3857 as in your case), see screenshot with rasters in the same CRS (4326) as project: enter image description here

Strange enough, setting the project CRS to 3857, leaving the rasters at 4326, it works well:

enter image description here

Apart from disturbing visually: is there a reason you want to change that? You need this small scale view? From my experience, this affects only visualization, not processing. So a workaround is to just ignore it. If you really need such small scale visualizations, you should reproject or change you project CRS. Fixing the bug - or funding it's fixing - would be a nice alternative: https://qgis.org/en/site/getinvolved/donations.html#

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  • Thanks for your help, babel. I am just using GeoTIFF for mapping on web, QGIS is useful for checking and viewing mapping result before uploading result to the web. – SCKU Jan 27 at 10:15

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