OK, I've thought long and hard in the past about asymmetric convergence.
I've said it doesn't exist. And I'm right, but I may be also wrong.
People converge as much as they need to. Doesn't matter whether they converge with normal ease, excessive ease, or less ease. They have to converge or be double. So, there's no "individual amounts of convergence"...everybody with the same p.d. (that aren't looking through spectacle lenses) converges the same amount. Whether it's easy or difficult.
But that's considering the convergence in total. That is, considering the binocular value of convergence. As in my big-head/small-head example above, I used binocular pds.
BUT WHAT ABOUT PEOPLE THAT HAVE CROOKED FACES!?
It is said that symmetry is beauty. Beautiful people are probably a nice 30/30 on their p.d.s. But poor Sarah Huckabee Sanders gets a lot of guff about her looks, and it's because her p.d.s are way asymmetric. (There are mean people on the internet, if you search around. In case you didn't notice.)
Maybe she's an alien and can look at two different people on opposite sides of the room at the same time?
From the looks of it, her right eye is hypo and I think a larger MONOCULAR p.d. She'd be something like, 33/30, right?
So let's do the monocular inset in her case, using the Optiboard Secret NPD formula (don't ask. It can and probably will fall into the wrong hands):
OD dpd = 33, npd = 31.35
OS dpd = 30, npd = 28.5
So, the best inset would be:
OD 1.65
OS 1.50
See the big difference! See how Sarah is suffering when she gets to +2.00! I don't either. What's the difference if she gets the "averaged binocular inset" of 1.57 mm OD/ 1.57 mm OS or the fancier, individually Autograph II+ method of 1.65/1.50? It's only 0.7 mm off in the left and 0.7 mm off in the right!
(And notice, if the older method were used, the right would be under-inset, and the left would be over-inset, both by 0.7 mm and the patient would compensate simply by turning their head slightly to the left. Does this matter? How many degrees of head turn does this involve? I don't know.)
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