I have a minor (-0.75) astigmatism only prescription.  When I wear my
glasses I tend to feel a little spaced out and sleepy and have
difficulty staying focused.  When I wear my contacts everything is
great, except that I have minor dry eye which makes it hard to wear
them longer than 12 hours, or outside in the wind, etc.  With both of
them my acuity seems good, and the glasses are better at night.  It
sort of feels like that in the glasses if I relax my eyes while looking
at stuff far away things either go out of focus or my eyes stop
tracking each other, or something.  This doesn't happen with contacts,
or with no correction for that matter.

I have two pairs of glasses with almost identical prescriptions and
it's worse in one pair than the other.  They came from two different
eye doctors.  Any ideas?  My only layman's guess is something to do
with the pupillary distance or some induced prism or something?  I
understand this type of thing is normally only an issue with high minus
power?  Does the RX machine come up with the PD, because I don't
remember anyone ever actually measuring.  Maybe I'm just crazy.

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