The fit values we get from our digital machines are wonderfully accurate, but they are most of the time used on plano frames. For mild Rxs no matter, but once we get into stronger Rxs as experience opticians we know the final pair is not going to look like the plano pair. Most recent case a -7.50 -2.00 OU, I'm putting him in 1.67 Auto 3 SV. I use visioffice and the values are good, but of course the demo lens is a plano 6 base, I'm going to get a 1-2 base lens back. Once I flatten out the frame a little to accommodate it the wrap is not going to be what it was in the demo. This is the biggest effect, but vertex is also impacted a bit. If the visioffice is perfectly accurate, its calculating the distance from cornea to eyewire. My actual lens is going to be at least 1.5mm center thickness, and if the bevel perfectly bisects the lens the back surface will be about 0.75mm nearer the cornea.

In this guy's case I did reduce the measured vertex by 0.75mm, and guesstimated a flattening of the measured wrap from 7.4 degrees to 3. (I will easily be able to bend the bridge slightly to get it to 3 degrees lens wrap, but bending it to 7 will look crappy and probably not perform as expected.)

1. Does anyone else worry about this, and make such compensations?
2. If we need to alter the "precision" digital values with out own judgment of the final form, especially in high Rx cases when accurate compensation is most important, how accurate are the final lenses?
3. Perhaps even fancy digital measurements and lenses are STILL only as good as your skilled optician, rather than the mall McTician operating the digital-face-measurer?