If you look at the image provided, you'll see that, as we move away from the OC of a lens, the power will change (in a lens who's power is not commensurate with proper base curves). My question is simple: Is there a formula that will tell you (theoretically) how the power changes the further you move away from that OC. And also..... If the power does in fact change, then would that not also affect the induced prism? Also also, the example that Darryl has illustrated is for a lens that is too flat for the power; what about lenses that are too round?
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