Does ring of shadows stack with Dith umbra?

[byrel]

Basically the title. I found a ring of shadows on a full-piety dith character. Do I get any benefit from the umbra on the ring? (I'm keeping it around for it's SInv rN properties anyhow, just wondering.)

[Berder]

It does not. You just get the benefit of Dith umbra (which is better than the ring umbra for other characters, by the way).