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I've only started using QGIS recently (used MapInfo). I would like to change the opacity of a heat map so that the areas within a political boundary has a different opacity than other areas. Would I use somthing like 'Select Feautres by Area' to select the area and then edit each smaller polygon indivdually?

Is this possible?

opacity-map

Stevan
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  • Not sure what you are trying to achieve. But if you just want to highlight areas inside specific boundaries, then using an inverted polygon fill to mask out the other areas is very easy. http://www.undertheraedar.com/2014/11/automatic-map-production-with-qgis.html – HeikkiVesanto Feb 27 '20 at 12:18
  • This looks a brillant way of achiving a focus on the areas I want to show the heat map data yet a bit above my ability level (at present) - thanks for sharing its much appriciated! – Stevan Feb 28 '20 at 12:11

1 Answers1

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It is easily possible when you have two different layers.

  1. First you can select the polygons that are within the admin boundary using the select within plugin.
  2. You can create a new layer from the selected polygons and another layer without the polygons that are inside the admin boundary.
  3. Later you can set different opacity for both layers. ( I generally use this option to set opacity for vector layers)
lawr
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  • Great solution - I would do this in graphic design work as well (why I didnt think of it here amazed me)... thanks for your time and help! – Stevan Feb 28 '20 at 12:13