Concentric circles, but not quite.

Question

Does anyone know how to easily reproduce an expanding pattern made of circles like this: http://i1.creativecow.net/u/181152/screenshot2011-09-01at6.35.16pm.png
Many thanks.
Richard.

Answer 1

Richard,
To avoid confusion, the term dots is used for the small filled circles here.
The distance between dots seems to be about the same as their size. This corresponds to 6 dots times the number of the circle (6 dots in the first circle round the central dot etc).
A  way that is more accurate than using the Polar grid is a Blend based on a single outer circle. The exact size and number of Blend steps depend on the desired number of circles/dots. For 61 circles round a central dot (with 366 dots in the outermost circle), you may:
1) Create a circle with Width = Height = 233 times the size of the dot, give it a Stroke Weight = the dot size, set the Cap to Round, tick Dashed Line with Dash = 0 and Gap = twice the dot size;
2) Ctrl/Cmd+C+F to create a copy and set W = H = 0;
3) Object>Blend>Options set Specified Steps = 60 (I always prefer to set Orientation to Align to Path unless specifically not, silly sometimes);
4) Select the two circles and Object>Blend>Make;
5) Enjoy.
If you have too many circles/dots, you may:
6) Object>Blend>Expand and delete the unnecessary ones from the outside in.
You may change the dot colour at any time.
It may be mentioned that the size of the outer circle is adjusted for the inherent inaccuracy of the circle shape.