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I've read all the posts and docs about the heatmap plugin but can't seem to get it to work.

The map is the size of the United States and has a little over 2000 points. I've tried small radi (1 meter) and large radi (5 million meters), but still get a red hot map.

I'm using QGIS 1.8 and WGS84. The data was initially in a spreadsheet, but I saved it as a .shp vector layer and deleted the old csv layer.

The goal is to convert that to contour lines to map density of these points like in this Mapbox blog post.

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It should work, its just a matter of using the right settings. However if you think it doesn't, if you look at the bottom of the tools help, you'll see a contact email address. He was quite responsive when I contacted him about some issues. –  GIS-Jonathan Nov 12 '12 at 11:23
    
Thanks and will do –  geraldarthur Nov 12 '12 at 15:42
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up vote 2 down vote accepted

I got back an email and apparently there is an issue with the current version of the plugin, v0.2. He forwarded me the text of another email but I wanted to give the highlights incase anyone else has similar problems with the heatmap plugin.

"I ran a few heatmaps myself and figured out that, there is some issue with Projection conversions. When the points are in a Geographic Coordinate System and when the buffer radius is set to Map units, it generates correctly. But when put in Meters for a geographic coordinate system it fails. I would suggest to convert the data to a projected co-ordinates."

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