Thanks to this post at the Animation Master forums I no longer have to worry about the edges of my rendered ray traced shadows looking grainy.
For years I had been wondering about why I could not clean them up but after I did a search on the forums I had the answer.
It’s an older post so I’m not sure why I never saw that post sooner.
Anyway, thanks to Robcat2075 and Fuchur for the information about the lights and shadows.