Originally Posted by
optical24/7
With your given Rx, vertex distance is going to be the biggest factor in magnification/minification. As lensman stated, steeper curves = more minification, the lens surface will be further from the eye than a flatter curve. You can make a -4.75 on multiple base curves. Best Form lens design would call for approximately a +2.50 front base curve to avoid peripheral and other lens aberrations. Using an aspheric design allows you to use a much flatter base curve, thus moving the lens surface closer to the eye ( creating less minification).
Again, as lensman stated, a stock 1.67 aspheric would probably be the best choice for this Rx if you were looking for as little of minification as possible. ( Stock lenses can be molded thinner than you can usually grind them and use an aspheric design to flatten the B.C.). Be sure to select a frame with as close of vertex as possible to keep the minification as low as possible.
( And yes, please don't try putting this Rx on a bi-concave. Epic failure is assured).
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