I have created a map of the United States with concentric circles around a geographic point, namely Detroit. I was able to give the different circles around the city colours of different grey shading. To do so, I used ArcMap's colours grey10-grey80. This is the result:
I have tried to reproduce the same map with a different colour shading. Ideally, I would like to have colour gradiation of different blue shades. The problem is that there exist too few and only very irregular predefined blue tones. I tried creating equal shades with ArcMap's colour selector but the result were irregular colours too. In the resulting map below, for example, some differences between the colours are barely visible, others are too large.
Because of that, I would like to ask if there exist any predefined shades of blue tones that give a clear (and aesthetically pleasing) result where differences are consistent and clearly visible like in the first (grey) map.