I have a raster surface that I kriged in Surfer and imported to Grass GIS but when I view it in QGIS, the null values outside of the interpolated surface take an extreme value and wash out the resolution in the rest of my surface. Is there an easy way to stop the null values from being assigned off the scale values?
Tell QGIS to treat those NULL values as NULL values: Go to Transparency tab and set the value there. This value will then be ignored when calculating color maps.
An alternative is to set min/max values manually using "Custom min/max values" in Style tab.