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How does one determine what map scale the XYZ Tiles are exporting their zoom levels at? I cannot seem to be able to configure a scale-dependent visibility to show labels and symbols on only specific XYZ Tile Zoom Levels.

For example: I am trying to configure symbols and labels to only appear in certain zoom levels for use in a leaflet map. I have been referencing the OSM Zoom Levels.

I have been testing with zoom level 11, which should correspond to 1:250000 map scale. I have configured my labels and symbols to have a scale dependent visibility from 1:249999 to 1:250001, which should only show such labels on zoom 11 on an XYZ Tiles export. QGIS properly shows these layers only on the 1:250000 map scale. However upon export the layers are not visible on zoom 11, which leads me to believe my zoom 11 is not exactly exporting at 1:250000.

I have also checked out this MapTiler website and confirmed that my XYZ Tiles export matches Google's tile names and bounds, which supports that the tiles exporting at 1:250000.

I have referenced some other questions which led me to play with the DPI on export, but this does not fix the issue either.

Any ideas? Am I missing something on how the map scale, DPI, CRS etc. and XYZ Tiles interact? How can I confirm that my XYZ Tiles are exporting as per the OSM Zoom Levels?

Edit: After much trial and error I have found for my layer to print only at XYZ Tile Zoom 11 (1:250000) at 96dpi (default), I need to have the layer visible to a Scale Dependent Visibility of 1:288895. I am not sure why there is a 15% difference between the intended and actual XYZ Tile Zoom Scale. Can anyone shed any light on this.

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  • I'm not sure if I follow. I am not importing tiles but exporting/creating custom tiles from a very large map. The Map Scale shown in QGIS doesn't seem to correspond to the Map Scale used by the XYZ Tile feature, since it takes a layer visibility of 1:288895 scale to display on the 1:250000 XYZ Tile Zoom Level 11. This is only necessary since an XYZ Tile export from zoom 5 to zoom 17 creates very wacky symbol and label interactions (they become absurdly huge above zoom 10), so I intended on duplicating each layer and manually adjusting each symbol and label to look nicely at each zoom level.
    – mapster
    Dec 20, 2019 at 21:48
  • Nevermind. I misunderstood your question. (I thought you were importing an existing XYZ tile, not creating your own.)
    – csk
    Dec 22, 2019 at 17:57
  • Ran into the same kind of issue on previous qgis version. Could you precise which kind of export you are using ?
    – kFly
    May 23, 2020 at 11:01

1 Answer 1

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QGIS does not use the OSM Zoom Levels Scales but instead uses Spherical Mercator Zoom Level Scales as shown on this page.

From this page you will see that Zoom Level 11 corresponds to a Map Scale (at 96 dpi) of 1:288895.85. Upon setting the scale-dependent visibility, the XYZ Tile label will now behave as expected.

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