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Author Topic: How 'good' is eyesight?  (Read 3869 times)

lyner

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How 'good' is eyesight?
« on: 15/07/2009 18:03:03 »
When I have a new pair of specs, they are fantastic. I feel that I could see individual molecules if I could just get close enough. I can read text on the bottom line of the chart almost perfectly and I expect to (and keep the optometrist 'at it' until I can).
But some people I talk to say that they never expect to get anywhere near the bottom of the chart and, when asked if they can read "that sign over there" they reply "No",  " Of course not " [implied].
They seem to have very low expectations of their sight.
Is their basic visual acuity actually that bad or have they just not sussed out how to drive the process of the eye test to get the best result for themselves?
I know people who are quire happy to go around with grot all over their specs, too. HOW CAN THEY?
Do they have visual faults that the NHS just doesn't regard as significant?


 

Offline RD

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How 'good' is eyesight?
« Reply #1 on: 15/07/2009 19:59:07 »
I know people who are quire happy to go around with grot all over their specs, too.
 HOW CAN THEY?


With your glasses on you can see they have got grot,
but if they are longsighted and only have one pair of specs with them,
then they canít see they have grot on their glasses,
coz without their glasses on they can't see things which are close up, like grot,


Do they have visual faults that the NHS just doesn't regard as significant?

If they are UK drivers then they must be able to ...

Quote
read the number plate on a stationary vehicle ... The distance requirement for the eyesight test using old style number plates is 20.5 metres or 20 metres if the new-style number plate is used. New-style number plates are easily identifiable starting with two letters eg AB 51 ABC.
http://www.direct.gov.uk/en/Motoring/LearnerAndNewDrivers/LearningToDriveOrRide/DG_4022529


... have they just not sussed out how to drive the process of the eye test to get the best result for themselves?

You've not memorised the eye chart have you ? :)
« Last Edit: 16/07/2009 23:43:08 by RD »
 

lyner

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How 'good' is eyesight?
« Reply #2 on: 15/07/2009 22:01:19 »
If their glasses are covered in grot then they are not seeing things (close or distant) as well as they could.  Yes, I take your point about not being able to see the grot  (or even see your glasses!) if you're long sighted. But recently cleaned glasses will give better results than dirty ones. Do people not actually spot that?

You are surely not suggesting that the minimum requirement for getting a driving licence is anything like the desirable visual acuity, are you?

"Driving the test."  Memorise the chart? I mean make the optometrist give you the sharpest prescription they can, by  repeating the choices of lens they are giving you and not being pressured to accept less.
I don't think you're taking this seriously!!!!

These fora frequently carry threads about the resolution of the eye, based on density of nerves on the retina but I think there is far more to it than that.  For instance, by a certain age, if the images presented to the retina are glubby, it may lose its ability to resolve anything sharper. Optical testing is one of those things that can be made very objective and could pick up all sorts of minor and potentially serious faults. The pressure tests and the visual field tests are used but are the results, in fact,  treated seriously?  Would opticians do more business by pointing out any defects that couldn't be treated by purchasing new glasses?
All the test produces is a 'least worst'  prescription, not an objective performance rating.

Why do people need to spend £££ on HDTV if they can't even read the text on the screen, or the labels on the TV set?
My question was actually a serious one and I should be interested to know how good the population's  vision is and why the inadequacies don't seem to be picked up. I do know that many people seem to regard the eye test as a test of THEM, rather than of their eyes. They seem to be interested in getting it over with asap as long as they satisfy the optometrist. Too damned humble in front of a 'professional', I think.
So how bad does it have to get before it's spotted and acted upon?

« Last Edit: 15/07/2009 22:06:13 by sophiecentaur »
 

lyner

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How 'good' is eyesight?
« Reply #3 on: 16/07/2009 20:43:16 »
What people don't seem to appreciate is that the best you can do even with glasses varies a lot from person to person. The attitude seems to be "I don't see so well, therefore I need glasses".
Can that be right?
OK, there may not be much that can be done about it but it could, at least, be acknowledged.
Any opinions? (Even  informed ones.)
 

Offline techmind

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How 'good' is eyesight?
« Reply #4 on: 16/07/2009 21:01:42 »
When I see people wearing filthy fogged-up glasses I really want to take them off and wash them and show them what they're missing.
But when the people are more senior than me at work (especially my old boss) I bite my tongue!
 

lyner

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How 'good' is eyesight?
« Reply #5 on: 16/07/2009 22:40:52 »
But, perhaps they can't tell the difference.
 

Online Bored chemist

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How 'good' is eyesight?
« Reply #6 on: 17/07/2009 15:05:53 »
With my glasses on I have 20/10 vision in my left eye and 20/20 in my right. (without them I can't see the chart, nevermind read it).
So there is some known standard for the average quality of vision. Presumably, like many other things in biology, there's a spread about that average.
 

lyner

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How 'good' is eyesight?
« Reply #7 on: 17/07/2009 16:56:30 »
I see that.
My problem is that the distinction is not made between the correctable defects and those which can't be corrected.
If you have a photograph and you not happy with the quality, you would look at the lens quality, the resolution of the sensor and the printing process. If you had a posh lens but 1MB camera sensor or (as with many phones) a 6MB sensor and a cruddy lens, you could end up with poor pictures.
If you are 'good' at doing eye tests you stand a better chance of a more suitable prescription - naturally.
But the only thing you get from a regular eye test is instructions for someone to sell you more glasses.
Is there really no possibility of getting 1. A properly objective test. And 2. Help and advice or even treatment to improve your potential acuity?
 

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How 'good' is eyesight?
« Reply #7 on: 17/07/2009 16:56:30 »

 

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