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I am having trouble with this raster layer that I downloaded from PASDA website - "Birds Habitat 2006 - Natural Lands Trust"

The attributes values habitat quality ranked 1-10. It looks like the background of this raster image (solid brown) have been assigned one of the values. I tried making the background value transparent - but I lose some of the actual data on the raster image that that value represents.

enter image description here

But if I zoom in close enough to the image the background disappears and the layer appears correctly. enter image description here

How to get this this layer to appear correctly?

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    – PolyGeo ♦
    Feb 8, 2017 at 1:45

1 Answer 1

Reset to default
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What are the values of the background pixels?

If you have valid values between 1 and 10, and that background is different, you can tell QGIS to use the value of the background.

Also, I note that the rivers look the same colour, so maybe it's value refers to 'other'. You could look into the metadata for the layer to find out.

But, really, I think you want to set the number that is used as the dark brown to be NODATA in QGIS, which will make it transparent.

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  • Looking at the data, the surrounding areaa seem to have a value of 128. So set that as an additional transparent value under Properties, Transparency tab.
    – AndreJ
    Feb 8, 2017 at 10:24
  • Good to know, @AndreJ, mark this answer as the solution if it worked, please. =)
    – Alex Leith
    Feb 8, 2017 at 22:01
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    Thank you both for the responses! AndreJ -My No Data value was set to 255 - I added 128 and that fixed it. But where/how did you find/determine the value of 128 was needed? Thanks again!
    – joe d
    Feb 10, 2017 at 14:50
  • Hi @joed you can interrogate the raster in QGIS (use "i" info tool) and find out.
    – Alex Leith
    Feb 12, 2017 at 1:57

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