Prescribed vs. actually measured diopters/cyl in my glasses

I have 9 pairs of glasses that I bought from optometrists over the course of many years. I remember what the prescription was for each when I ordered them, but thought to verify it nevertheless.

Today I went to two optometry stores to check the glasses to measure their actual lens diopters. I was amazed to find out inaccuracies between what should have been and what is there:

  • Glasses that were supposed to be -7.25 both, were measured as -7.25 (L) / -7.50 (R)
  • Glasses that were supposed to be -7.50 both, were measured as -7.75 (L)/-7.50(R)
  • Glasses that were supposed to be -8.00 both, were measured as -8.00 & -0.25CYL 015 (L) / -8.00 -0.25 CYL 001(R)
  • Glasses that were supposed to be -9.00 both, were measured as -9.00 & -0.25CYL 165(L) / -9.00 (R)

Is it normal to have these inaccuracies? Does it make a difference? Why are there differences?

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Lots of people do things half-assed and are bad at their jobs.

I care about that sort of thing. If you read Optiboard, there are a lot of opticians who laugh when they see a prescription like -8 & -0.25 CYL and will fill it as -8 every time (in that case they might actually be doing you a favor.) Their rationale is that the patient who can detect the difference between -8 and -8 & 0.25 CYL hasn’t been invented yet.

Somebody looks in the box of lenses and sees that they’re supposed to make glasses that are -9, but there is only one -9 lens left. So they use one -9 lens and one -9 & -0.25 CYL lens because they don’t think anybody will ever know the difference.

If you order 7 medium steaks and one medium-rare steak, there’s a pretty good chance the kitchen will make 8 steaks and your waiter will pick one and call it “medium rare”.

Low ethical standards and cynical workers who don’t care about quality control makes for shoddy products. The whole industry is largely a scam or a racket.

Oh goodness. Unreal! And really is annoying. Especially that I want to do the reductions properly, 0.25 at a time. So it means that these two pairs of glasses with the 0.25 difference between them, will need to be replaced.

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I haven’t purchased a lens clock, but I kind of want one.

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I agree, it’s extremely frustrating. Just because most people can’t tell the difference and don’t care or will never find out, it’s terrible to spend money on something and have an unscrupulous seller substitute something else that won’t even work for your intended purposes.

Wow! I had no idea its a thing!
As a side note, I went to three optometry stores today. One store wanted to charge me $20 per pair of glasses just to verify the lenses. So annoying. The other two stores just went and checked no problem. I have so many glasses, I am breaking them down in batches, lol :slight_smile:

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:cry: The thing is people don’t even think about questioning the end products’ quality :cry:

This looks like a cool gadget. Honestly. :relaxed:

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