H-Alpha Plane Problems

@lveci

I think the Alpha-Image is inverse. Because for example waterbodies should have a quit high Alpha. But in my images the Waterbodies have the lowest Alpha.
Is this right? And if yes, is there anything I can do to invert the Scale of Alpha in the Plot?
And the Entropy in Urban Areas in my Image is quit low.
But in a lot of books the Entropy of citis is high.
Is the distribution of DualPOL data and the H-Alpha Plane with the QuadPOL Data comparable at all?
I am really confused.

Thank you very much!