They can verify the prescription. Also in principle they could use the same machine that finds the prescription, to verify that your net correction is zero with your glasses on.
I once proved that my wife got the wrong prescription by just holding her old and new glasses up at arms length and seeing that things looked way different through them. The glasses place agreed.
How would one have tested it instead?
They can verify the prescription. Also in principle they could use the same machine that finds the prescription, to verify that your net correction is zero with your glasses on.
I once proved that my wife got the wrong prescription by just holding her old and new glasses up at arms length and seeing that things looked way different through them. The glasses place agreed.
Ask you to read letters again... with your actual new glasses on so you can verify how good you can see.
When you get a car engine rebuilt, do they just diagnose, replace parts and then never start the engine themselves to verify it actually works?