any optometrists or opticians here?

[linux-works]

I have a question for those in the field.

recently, I went in for an eye exam to update my glasses.  its been a few years since I did that and my left eye needed more correction (in my current glasses).

we did the usual exam; they project the same letters (sigh) on the wall and have you read the lowest line you can make out.  I don't like this test (for lots of reasons) but I follow the dr's procedure since he seems to think this is the best way to find your needed correction.

ok, he tries various len combos as he dials in this huge swing-arm mounted rotating set of diopter step-lenses.  'is one better or two?  is three better or four?'.  the usual thing (at least in the US, that's how they do it).

my issue is that we ordered the eyeglasses, the lenses were correctly ground but when I tried them on and had the new frames adjusted, the left was still not optimal.  I asked if we could try putting some fractional diopters in front of my left eye and if the 1/4 helped, lets just add 1/4 to the left and reorder the lenses.  using that sample 1/4 lens on my right did not help and actually made things worse, so I concluded my right is already properly corrected but the left needed an extra 1/4.

the doctor does not believe me.  I think he does not like that I questioned his 'big expensive machine'.

what do people in the field think about this?  I've found that the machine that they put against your face is NOT what you wear every day (lol) and so its a -starting point- but its not gospel.  once they order lenses and frame them, then adjust the frames so it sits evenly on your face, the distance between your eye and the lens can have an effect.  this is the last step in finding the -true- value of correction you need, given the lenses and frames you bought.

if you are in the field, I'd like to hear your comments on my experience.  I did finally convince the doctor to order a new left lens for me, but he clearly didn't want to and I was frustrated having to argue  with him.  my eyes don't lie and if that 1/4 extra helped, why argue with me, the patient?

[SeanB]

True, the best is to put on the finished prescription in a set of adjustable frames ( the optometrist should have those around) as a confirmation of the final script. Looks daft and feels very heavy on the bridge of your nose, but it does work well to verify. That way you can find out if there is any offset required for your eyes, and if the frames are correctly aligned.

Did you get glass or a polycarbonate lens, or one of the UHR formulations that make the lenses very light, as well as allowing you to have the photochromic coating as well. Transitions I or II or III are great, but as the index rises so does the price. Before the lens is ground to fit you should just take them and get the optical centre marked and do a trial fit, I had that with my last test. As well the Optometrist used a new Mac with a large display as a display, it is a lot better with doing the projector route, and gives a larger selection of images to use, along with some nice video you can use for checking the image is crisp as possible.

[linux-works]

to avoid color abberations, I always get regular old plastic.  not high index, which is thinner.  it takes 2 weeks or more to send it out (sigh) and the lenses are quick thick on the edges but the color bending is much less with plastic.

they charge me $70+ for an anti-reflective (AR) coating, which I would not go without, from experience.  I wonder how much markup is on THAT...

[corrado33]

I wonder how much markup is on THAT...

I used to work for the company that makes those coatings (as well as the transitions coatings). You wouldn't believe the markup on that stuff. I never worked in pricing but if I had to guess it'd be somewhere around 1000 %. They charged exorbitant amounts of money for their paints/coatings. They ordered the (few) cheap raw materials in HUGE double height pallets for ridiculous volume discounts. But, I guess that's how business works right?

[SeanB]

Same price worldwide, they have to pay for all the free samples to every optician worldwide. I went for Transitions II as I could not afford the III, which was double the price.

You do not want to know the markup on each step of that process. Suffice to say an optometrist who is good only has to do 5 patients a day to do well, and they are silly to belong to a chain, as there they are working to make somebody else rich. Of course paying can be a long drawn out process, as most insurers or medical aids take up to 6 months to settle, and will reject and require resubmission for any arbitrary reason.

[linux-works]

I'm aware of the very low cost mailorder glasses houses, but I've had enough iterations with the local doctor to know that going mail-order will just frustrate me and I won't end up with the quality I want.

so, I realize that they have to make their money somehow, to stay in business.

my 'bargain' frames are over $150 and I bet they are closer to $20 in cost (if even that).  plastic lens blanks are probably close to $5 each.  I will still continue to see the local guy but it would be interesting to know how much they do make on the products.

given that I'm paying over $70 for the AR coating, I won't feel so bad asking for a re-do, later on, if it chips or the coating flakes off.  I guess they can afford several redo's at that profit point!

[rob77]

actually it's not so trivial to manufacture a 100% bubble-less lenses , so it's not 5$ .... but they're still making a huge huge profit on those. they could easily provide a 50% discount and still making a shitload of money.

[jlmoon]

Hello Linux,

In my profession I have a optometrist I work with so I hang around their office quite a bit.  I have picked up on quite a bit of the technical details on eyesight along the way. 
A few questions,  how old are you?,  (reason for that - you could be in what they call the Tri-focal range).
If you're in the 40's or 50's you you could easily have a need for a Tri vision due to the errors in your vision at different distances.. ie;  > 8 inches to 12-14 inches, > 16 inches to 24 inches and then distance (driving optics). 
As we age we develop presbyopia which is where the elasticity of the eye diminishes and prohibits us from focusing on objects up close.  Unfortunately there is no solution for hardening of the eye tissue.  Just optical or dioptric  correction.
Do you have a astigmatic error in your left eye / right eye by chance?
if you do.. then you have what they refer to as slight Diplopia.  Diplopia is caused by the astigmatic error in one eye versus the other eye.. so naturally your brain tries to correct for this. 
This would be why you see better when you add that .25 diopter in your evaluation sequence.  Your brain is playing tricks on you (delay in perception / adjustment of vision).   Basically since your brain really does not know what 'clear vision' is due to the Diplopia..(and no true reference)  it is really difficult to get a calibrated vision standard that will stick.  I hope this clears things up .. no pun intended.. 

One more note, during the day.. depending on stress levels imposed on the eyes.. your vision can change upto .25 diopter throughout the day.

Best of luck

[linux-works]

I'm early 50's.

I tried progressive a few years ago.  tried it for a few weeks but could not get used to it.  they swapped those lenses out and tried bifocal/classic lenses.  I could not deal with that, either.  I know that I 'need' them but so far, I hack it by moving the glasses along the bridge of my noise.  yes, its a hack but at least it gets me non-windowed vision and I need long-distance clarity (for driving, mostly) more than I need mid or close vision.  I'll probably get VDT (computer) glasses later on that has a closer focal length.

what I did when testing the 1/4 diop lens was to stare out of the window and across the street at a sign.  relax my eyes and try to set to infinity focus.  flip between the 1/4 lens and no lens and the 1/4 really made a huge difference.  the right eye could read the sign just fine with the existing right lens; but the left truly benefited from the extra mag.

I do see variation as the day progresses or my eyes dry out, but I have to be able to see while driving and I consider that a priority over all other focal distances.

[jlmoon]

I'm early 50's.

I tried progressive a few years ago.  tried it for a few weeks but could not get used to it.  they swapped those lenses out and tried bifocal/classic lenses.  I could not deal with that, either.  I know that I 'need' them but so far, I hack it by moving the glasses along the bridge of my noise.  yes, its a hack but at least it gets me non-windowed vision and I need long-distance clarity (for driving, mostly) more than I need mid or close vision.  I'll probably get VDT (computer) glasses later on that has a closer focal length.

what I did when testing the 1/4 diop lens was to stare out of the window and across the street at a sign.  relax my eyes and try to set to infinity focus.  flip between the 1/4 lens and no lens and the 1/4 really made a huge difference.  the right eye could read the sign just fine with the existing right lens; but the left truly benefited from the extra mag.

I do see variation as the day progresses or my eyes dry out, but I have to be able to see while driving and I consider that a priority over all other focal distances.

I don't know how you're financially set but you might get correction for set diopter and then +.25. , sometimes having two sets of correction will do the trick.  I am 56 myself and have the same exact issues as you.  I have been studying the eye / correction phenomenon for quite some time and have resorted to using a good pair of 1.25 for close up reading / lab work and my prescrips for driving when my eyes are stressed.  Currently I am a Tri-Focal candidate, have presbyopia, diplopia and astigmatic error in my left eye.  Sucks Bigtime!

[pickle9000]

My mom has two detached retinas. Her focus changes daily, even more often on occasion. The eye specialist said to get a pair of "Emegensee". He said the visual quality was far from perfect but a good option for situations like hers. They are adjustable from -6 to +3D and make a big difference.

I have tried them and while they are not ideal they do work. They also look like crap.   

[jlmoon]

"Emegensee"

That's what some folks around here refer to as a "Amboo-Lance"!
 

[pickle9000]

Here is the websight (like the spelling?)

http://www.adlens.com/

[linux-works]

now THAT's what we need; variable focus lenses.

...add some wide/zoom ability in there and we have a deal!

[pickle9000]

Variable focus lens' that are electronically controlled would be kinda neat.

[denelec]

Variable focus lens' that are electronically controlled would be kinda neat.

Something like this...
http://www.aspexeyewear.com/collections/emPower

[pickle9000]

Variable focus lens' that are electronically controlled would be kinda neat.

Something like this...
http://www.aspexeyewear.com/collections/emPower

I was thinking more like an autofocus camera, pupil tracking and the distance checking.

[miguelvp]

Variable focus lens' that are electronically controlled would be kinda neat.

There is such a thing some usb camera used tech that did that. Not sure how it will scale to glasses.
On the adlens, I remember watching a TED talk about something similar, maybe it became that later on.

[pickle9000]

The glasses do appear to be from the same group as he TED video.



The neat thing about the "Emegensee" variation is that they are re-adjustable. The liquid filled ones have better visual quality but are only one time adjustable.

If a person had the inclination you could modify the "Emegensee" by driving the adjustment screws with a couple motors and using a rangefinder. Yes it would be weird looking but not unreasonable.

[G7PSK]

My mom has two detached retinas. Her focus changes daily, even more often on occasion. The eye specialist said to get a pair of "Emegensee". He said the visual quality was far from perfect but a good option for situations like hers. They are adjustable from -6 to +3D and make a big difference.

I have tried them and while they are not ideal they do work. They also look like crap.

Can't she have the retinas welded back in. It is certainly done here using a laser.

[amyk]

If a person had the inclination you could modify the "Emegensee" by driving the adjustment screws with a couple motors and using a rangefinder. Yes it would be weird looking but not unreasonable.

At what point does it stop being vision-correcting and start being vision-enhancing? I'd love a pair of autofocusing+zoom glasses. Working with SMD would get much easier.

[pickle9000]

My mom has two detached retinas. Her focus changes daily, even more often on occasion. The eye specialist said to get a pair of "Emegensee". He said the visual quality was far from perfect but a good option for situations like hers. They are adjustable from -6 to +3D and make a big difference.

I have tried them and while they are not ideal they do work. They also look like crap.

Can't she have the retinas welded back in. It is certainly done here using a laser.

Two years of laser until they (the doctors) said it just wouldn't work. Then we shifted to making her vision as good as possible. I am satisfied with outcome.