Help Cleaning up some plots

Hello, I have some plots I got from a simulation, which give me the results I should be getting. My advisor asked me to clean them up a little so I was wondering if someone knows of a good function in MATLAB to do so.

Basically I'd like to see if there is a convenient way to clean up some of these "smudges" and make the high values all the same color while making the low values all the same colors as well. A high/low pass filter might be the way but I am unsure if this will fix the smudges.

Thanks for any help!

[KSSV]

Have a look on imgaussfilt.