Anyone figure a cass secondaty using method of hindle if so i am looking for information regarding the ronci patterns inside and outside focus do they resemble under and over correction or are they reversed i assume the are the same how ever i am just looking for somone who has done it b4 and knows for sure i'm thinking if it looks overcorrected than there is too much correction to the secondary mirror and undercorrected would mean it is prior to hyperbola, is this the same a testing a sphere wihth a pinhole exactly?????