Gobos generally are used when a very crisp, well-defined edge is needed for a silhouette or projected object.

It has a well-defined edge that is not significantly worn, and the inner walls are terraced.

Black is circular with a well-defined edge, and inner walls that slope down to a small interior floor.

The rim is worn but still retains a well-defined edge.

The rim of this crater is mildly eroded, but still retains a well-defined edge and displays some old terracing on the wide inner walls.

This is a roughly circular crater with a well-defined edge that has not been significantly degraded by impact erosion.

The crater is circular in outline, with a well-defined edge.

The best-quality crown molding has crisp, well-defined edges.

Hayford has a well-defined edge that is not significantly eroded.

This is a relatively young crater with well-defined edge.