when you create a circle in sketchup, by default it only has 12 sides, but if you type in xs, where x is the number of sides you want, before you make the final mouse click to create the circle, it will have the number of sides you specify. for example:
click circle tool, click centerpoint on screen, drag mouse to size you want, type in oh...30s, and then click mouse again to set circle. the resulting circle will have 30 sides. Also in "view" you may have "hidden lines" checked.Which is great for working on the image, but not so great for "just lookin", hehe.