Dioptrx
It can be incredibly frustrating if you love astronomy but suffer from astigmatism. Fortunately, Tele Vue has created the Dioptrx range of corrector lenses for their eyepieces, including the popular Nagler series, in a range of diopter steps from 0.25mm to 3.5mm. These allow you to enjoy the outstanding views the eyepieces produce without the discomfort of wearing eyeglasses!