EVERY SINGLE ISTAR LENS IS INDEPENDENTLY TESTED TO ASSURE CONSISTENTLY HIGH QUALITY. WE USE TWO TEST METHODS, RONCHI, and INTERFEROMETER TEST (TESTED TWICE BY 90-DEGREE ROTATION TO OBTAIN THE MOST ACCURATE DATA).

WE HAVE INCORPORATED SPECIAL HEAVY (SHORT) FLINT GLASS IN ALL R30, R35 AND R50 DOUBLET DESIGNS IN ORDER TO REDUCE CHROMATIC ABERRATION AND INCREASE RESOLUTION.