Introduction

To get the highest quality heightmaps from QGIS we use the Print Layout function. This tutorial builds on the heightmap refinements taught in Export Heightmaps from QGIS by Screenshot.

Method

  Zoom in on the desired area

  Create a new layout

  Add a new map to layout. Move the mouse pointer over the page and click and drag to place the map

  Adjustments can be made by clicking on the map and dragging. The mousewheel can adjust the zoom. CTRL mousewheel will make finer adjustments.

Go to the Item Properties Tab

Change the Width and Height unit to px. Then enter the desired width and height. Use square dimensions.

If you intend to use the exported image as a texture to be rendered then Power of Two dimensions are preferred, 1024x1024, 2048x2048, 4096x4096 etc.

Go to the Layout Tab

Click Resize Layout

This will make the page match the dimensions of the map.

  Export as Image

Thoughts...

I haven't found a way to determine the best dimensions for exporting a heightmap. Trial and error is the method I use.