I am trying to figure out how to do gradient shading on some polygon noise contours that I have around an airfield based on their dB range. I understand how to break up features by their unique values into categories and use a gradient color scale, but I am wanting each new layer to "fade" into the previous without any clear distinction in a coninuous pattern. To give you an example, here is the map I am trying to reproduce:
As you can see, the layers are on a very nice gradient scale. There are only 9 layers that I have, one for 85, 80, 75, etc. I am not sure how to break it up this evenly and continuosly.
Here is what I have been able to do so far below: just used simple green/red gradient, took out the outlines and used transparency.