Originally Posted by
sharpstick777
Over the years I have heard many different answers to why SV finished lenses come with two numbers [ "68/70" being one example ] which one is true?
1) The blanks often have edge defects, the lower number is the lowest size, the higher, the max (if there is no edge defects)
2) The lower number represents V bevel lens uncut size, the higher, grooved or drilled rimless
3) the blank is decentered or elliptical, and the size is different depending on how its laid out.
What have you heard? There may be other mythical reasons. Which is actually correct?
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