[Qgis-user] unable to produce a raster mask

[Giacomo Fontanelli]

Dear community

I start from a raster layer, 8bit unsigned integer. Pixel value ranges from
1 to 12.

I would like to mask the pixels with value>8, setting their new value to 0.

I used raster calculator with this formula

 ( "lc_n_italy1 at 1" >= 8 )  * ("lc_n_italy1 at 1" * 0)

I tried also

 ( "lc_n_italy1 at 1" >= 8 )  * 0

but I always obtain a map with only "Nan"

Can you help me?

Thank you
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