I recently noticed that my 8" GSO RC has an issue, similar to astigmatism: all stars extend vertically on one side of focus and then extend horisontally on another side. Has anyone seen this with their scope? Is this collimation issue or maybe mirror cell issue? I know that 10" GSO RCs have very poor design of mirror cell, where they have only 3 contact points. Does 8" have the same issue?