One Lens at a Time?

[Andrew MacLean]

For centuries there was a conundrum that puzzled the greatest minds. "If reflection gives an inverse image, why is it that in a mirror you see your face with left and right switched, but top and bottom the same?"

I know the solution, and will offer it if anyone is eiven todistraction by the conundrum

Andrew

[新洲å°Â]

Can anyone explain why is there a need to insure contacts? Are they very expensive? Because I may have to buy them in the near future.. Someone, please enlighten me..

[jayuk]

Hi

Depending on what type of lenses you have, they can be VERY expensive!

Standard RGP Corneal Lenses are around £90 / lens, Rose K Lenses arouns £110, Scleral Lenses around £250 a lens, etc.

So it all depends on which type of lens you have, and how they are funded.

Hope that helps

J

[Sweet]

Ok i am intrigued now why is the reflection only reversed left and right in a mirror and not top to bottom?? Hehe Andrew you started this now so you need to finish!!

[Andrew MacLean]

Philosphers from the ancient Greeks to the most modern have puzzled over this question. Some have tried to offer a mathematical answer, but they have failed.

You have to stop thinking of the image in the mirror as a reflection per se, and start thinking of where you are standing as you look at your face.

You are on the inside, looking at what is on the outside. You are,. therefore looking at your own face as if from the inside, so that the reflected image is inverted right to left, but not top to bottom. Your internal orientation puts the reflected left ear exactly where it ought to be, and it also puts the top of your head esactly where it ought to be.

So Socrates, Sophoclese, Plato, Aristotle and the rest just needed to do a bit of lateral thinking and they's have solved their problem!

Andrew

[Sweet]

Hhmm but it is a reflection isn't it? Or are you telling me that i need to start looking at it as if i was looking at myself and not from being myself?!

Oh dam confusing but it would make more sense!! LOL!!

So water IS a reflection then right????

[Andrew MacLean]

On the contrary. We are precisely looking at ourselves from the inside. Think of a mask. You put it on and as it move stowards your face you see it from the inside. The effect of the image in the mirror is the same: it is as if you were looking at your face from the inside! It is only BECAUSE you are looking at yourself AS yourself that you see what you do.



Great fun, isn't it. The wonderful thing is that I discovered all this nonsense in good time to have them give me university degrees for playing silly games.

Andrew

[rosemary johnson]

Guys! ANy chance we can keep these threads on topic and chat in the Non-KC chit chat?

GOing back to being one-eyed and its effects:
Gareth, what you say about driving using cues if you don't have binocular vision makes a lot of sense.
Maybe it makes a difference if one was already a licensed, practiced, experienced, dare I say it skilled, driver before the KC took its effects and one became effectively monocular?

For ME, RFJ personally, I wouldn't try driving with only one eye and hence no distance vision. But then, I've never been an experienced two-eyed driver.
I started learning to drive when I was in the sixth form. I went to one lesson with only one lens, found I couldn't tell how far from the car in front I was, found it highly worrying and decided "never again!" Then I went to college, had neither the money nor the time for driving, then had 2 hydrops, and by the time I woud have had the time and funds for driving lessons, I was used to being monocular.
I have at times thought if the (then0 new lenses improved the vision, it would be worth trying to get my brain used to being binolcular again - but now I have lens sof different materials for each eye (RGP scleral left eye, piggybacking of RGP scleral over daily disposable soft lens right eye) and they just don't like having different things in them at the same time).

Maybe if I'd been a good driver already before the first experience of trying to drive with only one lens, I'd have coped far better? - or maybe without an instructor iwth dual controls, I'd have had a nasty accident.......

Interestingly, I never had "can't tell distances" problems when I used to cycle round London regularly - I think because when cycling one tends to look at the gaps between other vehicles, not the back of the one in front.
Similarly, I took my new "time-share" for a trot round the block laast Thursday, and that was fine too. But I do regularly have difficulties, and find it intimidating, negotiating crowded places (streets, or railway station concourses) because it's difficult to tell how much space there is between the other people. And sometimes when I've been out in a string of horses, telling when I'm the "right" distance from the horse in front - ie. not too close that the one in front gets annoyed and kicks my horse, not too far away lest car drivers try to overtake just mine and then tuck into the space between us (dangerous if they don't know horses well and try to tuck into too small a space and, literally, frighten the horses.)

Maybe we are all different in how well we adjust - but I do think it (ability to judge distances) is an issue that people who are asking if they can still drive need to consider. British roads are dangerous places....
Rosemary

[Sweet]

Sorry

Back to topic i've only had the use of one eye so i guess that it made it normal for me to drive like that as that is how i see. The DVLA do state that you only need one eye at 6/12 vision, but i would say that only you personally know how well you can see. If you always relied on two eyes to drive to suddenly drive with one would be very risky.

sweet

[jayuk]

I would have to agree with Rosemary here!...lol..whilst I do enjoy the somewhat eccentric replies and they do make me laugh; I think over the past few weeks we (including myself!) may have deviated from direct KC topics and responses.........so lets all give each other a kick up the back side and get back to what this place is.....one of the BEST Online KC Information Portals! -

Anyway - back to the lens; I actually have never had issues judging distances with one lens, and I have no idea why!....I am not sure if its because I am a good judge of my car and distance; or if my brain is actually filling in the unknown and making me assume distances!..Wierd but true!



J