55 year old female. Wears RGP contact lens. Was happy with the optics of the Spectralite series of lens. Now she is into multifocal and Spectralite is no longer available. We are NOT looking for...
I think I remember teaching myself that any lens tilt, due to the lens's thickness, requires the BI prism. It is indpendent of lens power. Just a slabby thing. But yeah, 1/2^ is what we always use...