Sadly not, the default values are -1000000.0, 1000000.0. I think this might be a shader issue. I can’t be sure since the tests I ran brought up some new issues but it looks like vtkVolumeFS.glsl
vec4 averageIPScalarRangeMin = vec4 (
if (all(greaterThanEqual(tValue, averageIPScalarRangeMin)))
I think this if statement will always fail since the tValue appears to have a 0 in  and . I did find this comment further down which is likely what needs to be implemented to fix this.
// One can control the scalar range by setting the AverageIPScalarRange to disregard scalar values, not in the range of interest, from the average computation.
// - We are comparing all values in the texture to see if any of them
// are outside of the scalar range. In the future we might want to allow
// scalar ranges for each component.
// - We are setting the alpha channel for averageIPScalarRangeMin and
// averageIPScalarRangeMax so that we do not trigger this ‘continue’
// based on the alpha channel comparison.
// - There might be a better way to do this. I’m not sure if there is an
// equivalent of ‘any’ which only operates on RGB, though I suppose
// we could write an ‘anyRGB’ function and see if that is faster.