If an artist or game director ever tells you that you need to add an "eclipse mode", it's actually pretty easy to do just by modifying your shadow map PCF kernel! Just set the weights to match the shape of an occluded disk.
@mjp Oooh so I guess what looks like aliasing on the right picture are actually crescent shaped shadows ?
@sobornost yup! You should see the crescent shape if you zoom in.