Spectacle prescription confusion.
Discussion
My other half does a bit of mystery shopping and she recently asked me to help out, by getting my eyes tested. As I am a spectacle wearer and was due a retest, I was happy to oblige. The task was to visit two opticians in the same day and have my eyes tested at both.
I've ended up with two prescriptions, which appear different. Having said that, they are written in different formats and I am struggling to work out what exactly is the difference between them. I'd be grateful if someone could explain the difference and perhaps advise on which prescription to have made up into spectacles.
I've ended up with two prescriptions, which appear different. Having said that, they are written in different formats and I am struggling to work out what exactly is the difference between them. I'd be grateful if someone could explain the difference and perhaps advise on which prescription to have made up into spectacles.
You're slightly longsighted with astigmatism in both eyes. The first one is so badly written it's impossible to tell what the prescription actually is as the basic correction (the 'sphere' number should be somewhere between +/-10 (usually). It looks as if he has written 175 which seems to be nonsense. It's possible to guess that it should actually be 1.75 but that is only a guess. If so then the two prescriptions are only 0.25 apart which is negligable. No idea which is correct though.
The other numbers are closer - the astigmatic correction is -0.75/-0.5 against -0.5/-0.5 (assuming the first optician doesn't know what a decimal point is) with axis angles of 90/90 against 80/90. Again close but I can see a 10 degree shift.
The 'near add' correction is again close at +2.0/+2.0 against +2.25/+2.25. Probably difficult to detect the difference outside the opticians room.
No idea which one is correct - you need to go to a third optician & see if you get a matching pair of prescriptions. There's a reason aircraft have three computers & a voting system!
The other numbers are closer - the astigmatic correction is -0.75/-0.5 against -0.5/-0.5 (assuming the first optician doesn't know what a decimal point is) with axis angles of 90/90 against 80/90. Again close but I can see a 10 degree shift.
The 'near add' correction is again close at +2.0/+2.0 against +2.25/+2.25. Probably difficult to detect the difference outside the opticians room.
No idea which one is correct - you need to go to a third optician & see if you get a matching pair of prescriptions. There's a reason aircraft have three computers & a voting system!
The difference in cyl/axis between the two prescriptions is not that much and if you test the same person ten times you will probably get ten different prescriptions.The first prescription has both a intermediate (VDU) addition and a stronger reading add which will focus closer.
There is a difference in the long sighted prescription of +0.50DS between the two prescriptions for the left eye which might be noticable.
Which one to get made up is a bit difficult and would depend on what you want the specs for, if they are varifocals I would tend to go for the second prescription as most long sighted people tolerate a prescription which is slightly weaker in the distance(because they can focus to compensate for it) rather than too strong(which blurs the distance), on a pair of reading specs probably not much between the two.
Probably in the end comes down to which test you have more confidence in, in terms of asking what you want to do with the specs and how close you want to hold things.
There is a difference in the long sighted prescription of +0.50DS between the two prescriptions for the left eye which might be noticable.
Which one to get made up is a bit difficult and would depend on what you want the specs for, if they are varifocals I would tend to go for the second prescription as most long sighted people tolerate a prescription which is slightly weaker in the distance(because they can focus to compensate for it) rather than too strong(which blurs the distance), on a pair of reading specs probably not much between the two.
Probably in the end comes down to which test you have more confidence in, in terms of asking what you want to do with the specs and how close you want to hold things.
Thanks for the helpful replies and explanations. Both prescriptions are different from my last, and I'm aware that the far sight in my left eye has got slightly worse since my last prescription.
I've tried varifocals in the past I couldn't get used to them. I normally have two pairs of specs -a pair of bifocals for for general use and a pair of distance specs just for driving.
The handwritten prescription was made by a man using sophisticated computerised testing equipment, and the printed prescription by a woman using the seemingly old fashioned 'frame on the face' in which she she manually changed the lenses. Both were very experienced optometrists
I've tried varifocals in the past I couldn't get used to them. I normally have two pairs of specs -a pair of bifocals for for general use and a pair of distance specs just for driving.
The handwritten prescription was made by a man using sophisticated computerised testing equipment, and the printed prescription by a woman using the seemingly old fashioned 'frame on the face' in which she she manually changed the lenses. Both were very experienced optometrists
I prefer to use "frame on the face" when testing because it is easier to observe the patient, but it all comes down to what you are used to. As an Optometrist with 20 plus years experience I know that you can't get it right everytime and sometimes you may have to adjust/remake a prescription.
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