The interferometer was purchased after the first batch of 130 SS scopes shipped. However, the scopes have a required minimum from the late Tom Back of 1/6th wave and 95 strehl. Thas has been his minimums since he started his company a decade or so ago. We have had reports through the roddier program of 1/10th wave and 99 strehl on more then one lens.

I believe the roddier test of the 111 brought around 1/8th wave and 98 strehl, but I could be wrong as I don't have the data on my desk.