question Glasses

Stereodude

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I'm sure I'm not the only person here wearing glasses. I'm thinking to get a new set of glasses to replace the pair I've been wearing for more than the past decade.

I see there are a variety of lens coatings and lens materials out there. Anyone have any comments or thoughts about any of them? What about photochromic lenses? Anyone tried those?

My current lenses have some chromatic aberrations that bother me, but based on my research CR-39 lenses are basically the best with regards to CA (tied with glass with the Abbe rating). :dunno:
 

ddrueding

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I do wear glasses, but I haven't done any research on the different options out there. I normally just go to the optometrist, let their receptionist pick out the frames, and then say yes to every option offered.

I should be getting a new pair soon, and look forward to any information your research returns.
 

Howell

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I just replaced a pair I'd had for a decade. My prescription is a little strong so my top criteria were look and weight. I've never tried photochromic lenses but they look a little goofy.
My previous pair made my vision a comfortable 20/15 but these are a little off that. What chromatic aberations are you seeing?
 

Stereodude

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I do wear glasses, but I haven't done any research on the different options out there. I normally just go to the optometrist, let their receptionist pick out the frames, and then say yes to every option offered.

I should be getting a new pair soon, and look forward to any information your research returns.
My current glasses have no coatings and are likely cheap CR-39 material, but I'm not really sure. From memory my eyes are either -2.25 or -2.75, not sure which so the lenses are not particularly thick. The thinner / lighter lens materials have lower Abbe ratings and are more prone to chromatic aberrations per my reading. The positioning of your eye and FoV to the optical center of the lens also impacts the chromatic aberrations per my research. It looks like Hoya has the best AR coating out there. Super HiVision EX3.

I just replaced a pair I'd had for a decade. My prescription is a little strong so my top criteria were look and weight. I've never tried photochromic lenses but they look a little goofy.
My previous pair made my vision a comfortable 20/15 but these are a little off that. What chromatic aberations are you seeing?
I guess I should clarify. Chromatic aberrations are probably not the right term for what I see. I don't see red / blue / purple fuzzy edges with black and white high contrast edges. Like black and white text under a broad spectrum light source is sharp, even at the edge of my glasses. What I notice is that objects illuminated with with narrow spectrum lighting or narrow spectrum light sources don't seem sharp some times. Like sometimes a distant LED traffic lights will look blurry to me at night if there aren't other illuminated high contrast edges nearby (like my eyes can't focus on it) but something equally distant under incandescent or another broad spectrum light will look sharp to me. I've also found that the image from some projectors (not most) will look blurry to me at a given distance, but when the overheard fluorescent or incandescent lights are turned on things are the front of the room by the screen are perfectly sharp. I realize depth of field and pupil dilation are related, but depending on the light source I can see razor sharp under similar lighting conditions, which would seem to rule that out.

I guess I can't definitely say that the glass are at fault, and not my anatomy.
 

Mercutio

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I need the lightest lenses I can buy because my eyes are god-awful. I've been talked in to getting the "computer screen" coating a couple times and I feel like there's a subtle loss to contrast in my vision for having it, so my last couple pairs have omitted the coating entirely. I sort of think the coatings are a scam.

I've been buying from SmartBuyGlasses.com. I have no complaints about the product or the service.
 

Howell

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SD, is it possible the focusing issue is eye hydration related? I've not experienced the symptoms you describe but eye hydration is responsible for a lot of the clarity.

Fwiw my numbers are nearly twice as big as yours.
 

Stereodude

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I sort of think the coatings are a scam.
The coatings shouldn't be a scam. I understand how they work from my jobs in the LCD industry dealing with AR, hydrophobic, and oleophobic coatings. A hardcoat should also not be a scam. I've only ever had pretty much the cheapest glasses you could get (whatever insurance paid for completely). I guess I will try getting a high end pair and seeing if they're perceptually better or not.
 

Stereodude

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SD, is it possible the focusing issue is eye hydration related? I've not experienced the symptoms you describe but eye hydration is responsible for a lot of the clarity.

Fwiw my numbers are nearly twice as big as yours.
I'm not sure. I don't think I have dry eyes. I haven't noticed the blurriness as much recently. I haven't ever determined or noticed if there's a pattern to it or not.
 

mubs

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I've been wearing glasses for 45 years.

Critically important, make sure the lens has UV coating for UV-A and UV-B. Or you'll get cataracts quite early. Other coatings are optional.

How the heck do you guys wear the same lenses for a decade? For a normal guy, you should get your vision tested at least once every three years, with dilation of the pupils. If you have health problems (diabetes, BP, etc.), every year.

I've been wearing progressives + photo-chromatic since 2000. The best lenses are frightfully expensive, but quite good. For progressives, Varilux is the gold standard. I've had second and third tier lenses from Costco before, and they're not as good. Strangely, or not so strangely, the very best progressives I've had was my first one, Varilux, from a private / independent ophthalmologist in Mission Viejo, CA, at full price. Everything else has been less than perfect.

You'll have best results if: a) they use the meter to measure pupil distance instead of using a ruler and b) you wear the intended frame with the dummy lenses and the center of your pupils are marked on the lenses with a marker. Results are compromised (loss of acuity etc.) if these are not followed.
 

Stereodude

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How the heck do you guys wear the same lenses for a decade?
My eyes haven't changed prescription, the glasses were never seriously damaged, and I've been quite lazy as a result.

However, they now show a fair bit of wear from the many years and it's time to replace them. Since it's my vision and I'm not living paycheck to paycheck or on my last nickel I don't feel the need to buy the cheapest glasses possible. Hence my interest in some of the higher end features.
 

Stereodude

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I've never tried photochromic lenses but they look a little goofy.
Yes, this has generally been my impression of them as well. Some of what I've read said they don't darken when driving in a car which would seem to defeat much of their usefulness. That's pretty much the only place I wear my prescription sunglasses.
 

snowhiker

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My eyes haven't changed prescription <snip>
I'm not living paycheck to paycheck or on my last nickel I don't feel the need to buy the cheapest glasses possible.

Since your vision is relatively stable AND you earn a decent living you should consider Lasik and be done with glasses for good.

My vision was approximately 20/200. Then in 2006 I got Lasik and went to 20/20. Amazing quality of life differences.

1) ALWAYS perfect vision. Wake up, in shower, in pool, stumbling around in middle of the night, etc.
2) No, "Where are the F are my glasses."
3) No cleaning glasses.
4) No tightening screws/replacing lenses that popped out.
5) No scratching, dropping, breaking, leaving in car, etc.
6) No goofy clip-on sunglasses. No separate prescription sunglasses.
7) No pushing glasses up as they slide down your nose*.
8) No nose or ear discomfort from glasses.
9) No "four-eyes" jokes. LOL.

Etc, Etc. Probably a bunch I forgot in the last 10 years. Many of the regulars here make a decent living and wouldn't think much of dropping a few grand on a new computer or gadget. Get the Lasik if your eyes are suitable for the procedure.


* I did this so often I was still doing it 9-12 months after Lasik just out of habit.
 

Stereodude

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Since your vision is relatively stable AND you earn a decent living you should consider Lasik and be done with glasses for good.
I'm not interested in Lasik. Degraded night vision doesn't interest me. That and the fact that I'll still need reading glasses makes it basically pointless, especially as someone in my mid 30's. So I could get it done and be glasses free for maybe all of a decade if I'm really lucky? No thanks! Lasik sounds like a better deal for someone right out of college, who could be glasses free for 20+ years, not someone who will need likely bifocals in a few years.
 

Stereodude

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So I was trying to find actual customer reviews of photochromic lenses, specifically the Transition Signature 7, since they're supposed to be the latest and greatest... Either my Google-fu is totally lacking or it's all AstroTurf out there. There are a few "reviews" here and there, but they aren't the slightest bit believable. They read like a regurgitated take on the marketing material.

I also couldn't find a single chart of time to clear at different temperatures. Pretty much all the videos show how fast they'll turn dark in the sun or how dark they get, but don't show how long they take to become clear once you go indoors, which would be my primary concern. I don't want to be the moron who looks he's wearing sunglasses indoors because they're still dark after 10 minutes of being inside, not to mention I do have a reasonably strong preference to seeing clearly when I walk indoors.
 

Howell

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Lasik sounds like a better deal for someone right out of college, who could be glasses free for 20+ years, not someone who will need likely bifocals in a few years.

Or wait until you need lens replacement and potentially live out the rest of your life with neither types of glasses.
 

jtr1962

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How the heck do you guys wear the same lenses for a decade? For a normal guy, you should get your vision tested at least once every three years, with dilation of the pupils. If you have health problems (diabetes, BP, etc.), every year.
I've had the same glasses since my early 20s. That's when my parent's insurance stopped paying for glasses or eye exams. Given that I only need glasses when watching TV, I haven't had much incentive since to get an eye exam or a new pair. I might finally look into it soon given how ratty my glasses are getting lately. Last test I had my vision was around 20/200 (left eye is worse). Still good enough to ride a bike or walk without glasses but not for anything requiring better resolution. I sit close enough to my monitor so it's clear but that's not practical with a 40" TV. Close-up vision is still great. I can read the numbers off 0805 resistors with no problem.
 

Handruin

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I just went through the process to get updated glasses. I have a fairly strong prescription for both eyes in the -10.25 and -11ish. Due to this, I'm restricted/constrained to certain dimensions of frames to reduce the amount of thickness on the edges. The optometrist I use typically deals with lens from Zeiss and I get their single vision lens. I get the higher index at 1.74x to reduce thickness and I do see a decent amount of shift in light (higher dispersion/color fringe) when looking at things off-center. The lenses have AV and anti-reflective coatings in them. I've had their lenses in my previous pair of glasses and they've held up really well over a few years of daily use. I've had Essilor lenses in the past with Crizal coatings that have flaked off but this hasn't happened with my prior Zeiss lens which I think uses a different AR process. I'm sure Crizal has come a long way since I last had a poor experience so take that with a grain of salt.
 

Handruin

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If those are diopters, -10 is quite a high negative correction. You should be able to see the tip of your nose and not much else. :)

Not quite that bad but seeing is challenging without glasses. One eye is a -8.75 - 2.0 and the other is a -9.25 - 1.75. Maybe my doc said the wrong thing but he just subtracted the numbers and gave a total.
 

jtr1962

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I just took this vision test out of curiosity. I used 10 feet for the distance. Uncorrected is around 20/125 in the left eye and 20/100 in the right. With my existing glasses it was 20/25 and 20/20 corrected, respectively. This had more to do with the left lens having fine scratches than anything else. While this obviously can't substitute for a real eye exam, good to know my vision hasn't gotten significantly worse in 30 years.
 

snowhiker

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I'm not interested in Lasik. Degraded night vision doesn't interest me. That and the fact that I'll still need reading glasses makes it basically pointless, especially as someone in my mid 30's. So I could get it done and be glasses free for maybe all of a decade if I'm really lucky? No thanks!

I've noticed my "reading vision" start to go south when I turned 47. Someone else might need them when they turn 55. Who knows. I can still read for the most part without reading glasses, but if I'm reading a book or reading very small print I need reading glasses. But 95-99% of my "awake-time" I'm NOT reading and I don't need glasses.

There's even a new procedure, "KAMRA inlay," that can eliminate the need for even reading glasses.

LASIK or LASEK do not automatically reduce/impair night vision. Lots of improvement from 10 years ago in both methods and laser technology. Depends on pupil size. If your dilated pupil becomes larger than the LASIK treatment area of the eye night vision problems (blurriness, starbursts, halos) can occur.

"Newer wavefront-guided lasers have clearly established that the vast majority of these patients can now be treated without causing problems with night vision. In fact, using the VISX wavefront guided laser that we favor, a large percentage of patients in the FDA trial actually IMPROVED in terms of night vision. This is why the US Navy and Air Force believe in this technology for its fighter pilots." quoted taken from here. Quote is from one doctor and anecdotal in nature but worth investigating.

If you read or someone told you LASIK effects night vision 5, 10, 15 years ago, it couldn't hurt to see what the percentages of effected patients exist today. Might be lower than you thought. Plus with a newer treatment technology and if you eyes are suited for it, you may have a near-zero chance for effected night vision.

Lasik sounds like a better deal for someone right out of college, who could be glasses free for 20+ years, not someone who will need likely bifocals in a few years.

I thought this as well, that I'd only have a "few good years" before my vision went bad. But vision declines a bit from say an age of 22 to 35 years old before leveling off and stabilizing. So it might actually be a bad thing to get vision correction "too early." You correction vision would be off by your mid-30s. So mid-30s is actually a good time to do it.

And how much are your "high-end" glasses with good lenses going to cost? $200, $300, more? How long will they last? What's the total frames and lenses cost for next 20+ years? Plus cost of prescription sunglasses.

I paid $4600, 10 years ago. I did zero research of procedures and methods. I went here for my procedure, only because I saw a magazine article that listed 125 other doctors (or their family members) that went to these doctors for their eye procedure. I figured if docs went to these docs they must be good.

Point being, it might be lower cost for you today. Better procedure with lower cost, reduced more by not needing to buy glasses, and LASIK makes more sense.


And Yes! For me the quality of life improvements of not having to wear glasses are worth the cost. I only wish I had the procedure 5 years earlier.
 

Howell

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Not quite that bad but seeing is challenging without glasses. One eye is a -8.75 - 2.0 and the other is a -9.25 - 1.75. Maybe my doc said the wrong thing but he just subtracted the numbers and gave a total.

In your case the second number may indicate cylinder or astigmatism. I thought my prescription was challenging at -5 or 20/400. Though it could be worse; the scale goes up to at least -20.
 

Howell

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I bought my most recent pair at glasses.com which did not offer very many options. After the lightweight lenses the only option was photochromatic which I declined.
 

mubs

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SD:

1) my transitions DO get dark inside the car, depending on how bright it is outside. Since it darkens smoothly, one doesn't notice it, and I am often surprised when I look in the mirror and see that they have darkened.

2) They lighten up in about 2-3 minutes once you come indoors. This is not quick enough sometimes if the place you're entering is not bright, and at these times, I take my glasses off so I can see; better to have blurred vision than not be able to see anything at all. Despite this, and despite going through repeated turbulence in my finances, I've always opted for photochromic lenses since for me it does make a difference and is worthwhile.
 

ddrueding

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Lasik is on my short list. I normally pay $1k without insurance for my glasses, (plus another $700 for sunglasses) and they last a couple years before I bother to go back in for another appointment.

The reason for the sunglasses is that my transition lenses do not change at all in the car. I believe they are triggered by UV and my current car has full UV protection on all the windows. Occasionally I'll leave a window cracked and end up with a hilarious stripe of dimmed lens. It clears within a minute or so; I've never noticed it once I go indoors.
 

Stereodude

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The reason for the sunglasses is that my transition lenses do not change at all in the car. I believe they are triggered by UV and my current car has full UV protection on all the windows. Occasionally I'll leave a window cracked and end up with a hilarious stripe of dimmed lens. It clears within a minute or so; I've never noticed it once I go indoors.
Which exact photochromic lenses do you have?
 

Stereodude

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Might be more a question of what he has applied to his car windows? ;)
Nah, because that's not a relevant question to me. I was most curious because he said they clear up in a minute or so, which is my main concern with photochromic lenses.

FWIW, most car windows block a very high percentage of UV light, which is how most photochromic lenses work. However, the UV blocking in windows does degrade over time, so an older car may let enough through to allow some darkening. However, I also have tint on all my car windows, including the windshield. I have no expectations of a traditional photochromic lens getting dark in my car.

You can get photochromic that is activated by visible light as well as UV: http://www.drivewearlens.com/
And they're probably not well suited for wearing indoors. They seem like light level sensitive sunglasses.
 

jtr1962

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And Yes! For me the quality of life improvements of not having to wear glasses are worth the cost. I only wish I had the procedure 5 years earlier.
I think the value of getting Lasik depends upon what you wear glasses for. I've read Lasik will correct your distance vision but not the range over which your eye can focus. As a result, your near vision will suffer. 99% of what I do involves near vision. That includes working on electronics, reading (both paper and a monitor), even seeing my food. On the flip side, the only thing I wear glasses for is watching TV. My distance vision is plenty good enough to walk or bike safety without glasses. I can't read street signs until I'm fairly close, but I see anything I need to avoid hitting just fine. Given all that, Lasik would be pretty much all downsides for me. I would have nice clear vision walking, riding my bike, or watching TV, but I would probably need to use reading glasses for all that close-up stuff I do. Any type of lenses cause unacceptable distortions at close range. I would end up being a lot less efficient at the things I do on a regular basis. They wouldn't be pleasant, either.

I'm actually curious in this day and age where everyone stares at screens, often inches away, why we even consider having good distance vision as a desirable default. It makes more sense to me to have to use glasses for the relatively rare times distance vision is important.
 

Howell

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If you want to see a fast moving dog or fast moving car with enough time to avoid intersection you better have good enough distance vision. I can't think of anything that would be an example of close, high speed work. For everything we have magnifiers.
 

Stereodude

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I also can't think of a situation when I wouldn't mind everything being blurry when I glance up. Things start to get blurry about 1 foot from my face without my glasses.
 

LunarMist

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My distance vision is still good so I only need glasses for near vision. Maybe Joe is always living up close, but overall it is better to not need distance correction. I pass the visual driver's test in the machine easily, even the smallest line that is below what they ask for. At least I don't need glasses immediately to get out of bed as some people do or perform basic activities around the house. The first time I put anything on is usually to check the e-mails or review expiration dates of cold-chain products. At one point about 20 years ago, my distance vision was a little off and the Ophth lady explained that I was straining my eyes with close work and needed some slight magnification for reading, etc. Within 3 months my distance was much less strained, and has been for decades since. I have several pairs of glasses. One progressive and one intermediate pair of glasses are from the optometry place and the other single vision glasses were much cheaper and purchased online. I have no astigmatism, so the fitting of the online glasses is rarely an issue. I have a few different values for different purposes, since the progressives are not my favorite for computer use.
 

jtr1962

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If you want to see a fast moving dog or fast moving car with enough time to avoid intersection you better have good enough distance vision. I can't think of anything that would be an example of close, high speed work. For everything we have magnifiers.
I see things just fine in those situations, at least well enough to avoid them. It's not important for me to see details on a car or dog, so long as I see it. I'm not sure what the minimum vision you need for that is but I think anything 20/200 or better is good enough. I can easily see cars 3 or 4 blocks down when crossing a street. That's more than enough to be safe.

Magnifiers create their own distortion and other issues. For that reason I've always found it difficult to work with them. They also only magnify a small area at once. That makes them cumbersome to use on something like a circuit board. I have to use them sometimes with SMD components with very fine pitch to check for things like solder bridges which can't be seen with the naked eye but in general I prefer not to use them. I end up with a pretty bad headache after using one for a while.

I also can't think of a situation when I wouldn't mind everything being blurry when I glance up. Things start to get blurry about 1 foot from my face without my glasses.
For me things start to go out of focus at maybe 18 or 20 inches but I still see things in the distance fine at a macro level, albeit with some details blurred. Ideally, I'd love to be able to focus over a range from maybe 2 or 3 inches out to infinity but my eye lens can't accommodate that. I need to see fine details for reading or circuit board work. It's not particularly important for anything else I do.

My late father had much worse vision than me. He once bumped into a lamp post without his glasses and said "excuse me, miss". He didn't need reading glasses however even when he hit 70. If my vision was that bad I might consider having Lasik to correct it enough so I might still have good near vision while also having distance vision which is functional enough for most tasks without glasses (~20/100 or so).
 

jtr1962

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My distance vision is still good so I only need glasses for near vision. Maybe Joe is always living up close, but overall it is better to not need distance correction.
I've pretty much always done mostly close tasks, like building models, circuit board work, etc. I never went into "ball" type sports where I would need good enough vision to see a ball coming at me from a distance. That and driving (which is something I don't need to do, either) are about the only two tasks which some large number of people engage in regularly which require good distance vision. You don't need perfect vision to walk or ride a bike or go about most other daily tasks. If there were no compromise of near vision then it wouldn't matter but I'd rather be able to see objects 4" away clearly than 40 feet away.
 

LunarMist

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I've pretty much always done mostly close tasks, like building models, circuit board work, etc. I never went into "ball" type sports where I would need good enough vision to see a ball coming at me from a distance. That and driving (which is something I don't need to do, either) are about the only two tasks which some large number of people engage in regularly which require good distance vision. You don't need perfect vision to walk or ride a bike.

Of course it is not absolutely needed, but I prefer to see everything as clearly as possible. :) Vision is one of the few senses that can be well corrected inexpensively and noninvasively.
 

jtr1962

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Of course it is not absolutely needed, but I prefer to see everything as clearly as possible. :) Vision is one of the few senses that can be well corrected inexpensively and noninvasively.
Right, and I have my glasses if I want to see clearly in the distance for whatever reason. I may even get a new pair after reading this thread. I'm just happy that I can use my naked eyes for 99% of the tasks I do regularly. Watching TV is typically the only time I put on my glasses.

If I needed perfect vision for riding my bike, I'd probably have to opt for contacts. Glasses are majorly cumbersome to wear on a bike and tend to fog up when you're exerting yourself.
 

RWIndiana

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I know no one seems interested in eye surgery, but there is an alternative to LASIK. I wasn't the greatest candidate for laser surgery myself, so I opted for IOLs (Visian ICLs) and I am very happy with them. The healing time is much faster than with LASIK, the visual clarity is better than I ever had with glasses or contacts, and the surgery is completely reversible, so when I start to lose my ability to read close (I'm 33), I could get them exchanged for something better. They actually make a lens that will focus for you, much like your own natural lens. But usually it's cataract patients who get those.
 
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