I'm generally wary of anyone who says they're a perfectionist, because I usually find them to be absurdly picky about silly things for no real reason, but this guy has a point about not being able to tell if glasses are right for you based on staring at some letters.
Making My Own Glasses
101–110 of 189 posts
Re: Making My Own Glasses
#102> Do you remember the process in which an optician makes you wear a new pair of glasses and stares at you with this optician-look, takes the pair of glasses away from you again, goes to the back office and starts bending parts of it in a seemingly random manner, comes back, hands you the pair of glasses which now suddenly fit perfectly? Yeah, I attempted to do that with my new pair of glasses and noticed that I suck…
Unfortunately, lots of places will refuse to fit/bend your glasses unless you got them from their stores. It’s just easier and less of a hassle for them to have a blanket ban vs worrying about breaking the person’s glasses and being charged/sued for it.
Re: Making My Own Glasses
#103> Optician: “Now with this lens, do you see better or worse?” > O: “Honestly, I have no clue. Maybe. Maybe not? The letters look similar but different.” [edit] Reprahsing to make it clearer: will it be possible in the future to measure objectively?
Since vision happens mostly in the brain, simply selecting a lens which focusing light at a certain point in your eye is not the only thing to optimize for. You also have to optimize for the processor behind the sensor which, at least until more advanced vision models are made, is going to be purely subjective.
Is it possible for the lens to focus light perfectly, and the brain to process that as blurrier than if the light were focused imperfectly?
I would imagine that, no matter how the brain were processing the image, the image being focused exactly on the retina is an objective truth, and that an exactly-focused image must be clearer to the brain than a blurry image.
Re: Making My Own Glasses
#104Earlier quoted context omitted.
Yes, I am a doctor. As far as I remember, I studied medicine and graduated. As other comments point out, medicine is a very specialized field nowadays and I didn't specialize in any field (I got into coding healthcare software instead) - in Germany you study all disciplines at University (min. 6 years) and then specialize during something comparable to US residency in a hospital. I understand the process of accommoda…
If I may, particularly as a doctor yourself, you should call the eye doctor "ophthalmologist", as you surely know if you use "part of the body + doctor" there might be issues should you report a visit by a "proctologist" ...
Why replace a good, short and clear word with a bad and long word that adds no information, but fewer people will understand? [Edit: I think I'm wrong about the adding no information, depending on country there might be other types of eye doctors than ophthalmologists]
Re: Making My Own Glasses
#105Earlier quoted context omitted.
Inter-pupillary distance is among the few things glasses related that can be measured yourself.
That may take some practice. I did it myself once, and was off by about 4 mm. The resulting glasses were incredibly painful. My eyes would try to look in two slightly different directions, and my brain would put the wrong 3D picture together. Whenever I moved my head my eyes would readjust, which took a noticeable period of time, and I could literally feel my non-dominant eye turning itself to find the focus. I chuck…
When I bought online from Zenni optical they sent a plastic ruler that you set on the bridge of your nose with a slot in the middle, and can be used to measure PD. It's similar to this: https://store.eyeque.com/eyeque-pd-ruler.html
Re: Making My Own Glasses
#106I wonder if the use of a lensmeter makes you fall into a local optimum while missing out on a potential global optimum?
Let's say I go to a bad optician and get a pair of lenses that have something way off like the cylinder is the wrong way around, or toric lenses for astigmatism when you actually don't have it. Everything looks like crap but then you get used to it (the brain is amazing at adapting). Then a few years later you go get another pair, and they use the lensmeter reading as the baseline.
I think I have astigmatism, or do I? It took me more than two months until I stopped getting headaches after getting my first glasses and I could see decently. Every glasses since then are based on that first reading. Maybe I've just become used to it, and there exists a significantly better lens that I could become used to as well.
Re: Making My Own Glasses
#107Earlier quoted context omitted.
Eh... he provided custom specifications to a manufacturer. Apple makes it's own SoCs for the iPhone, only Apple can't make semiconductors. They provide specifications to a manufacturer. Apple makes the iPhone, except it's Foxconn that manufacturers it. The APU in the Xbox One is made by Microsoft, but it's composed primarily of off the shelf designed CPU and GPU cores from AMD and manufactured by TSMC/GF/ .
By this logic, I am “making” my own pizza every time I tell Dominos to make me a 20cm pizza with cheese and sauce. I am “making” an IKA sofa when I order it online, telling the manufacturer the model, the size (2 seat, 3, etc). No, what the OP did was check/confirm his numbers and then bought a pair of glasses from a website. Many people buy them from websites, typing in the numbers they received from their doctor. N…
I don't disagree with you, and the line between ordering and making is fuzzy.
Your examples of an Ikea Sofa and Pizza are great examples of either end of the spectrum. An Ikea sofa has finite configurations that could all be permuted into model numbers, the parts are interchangeable and swapped between models, and prefabricated. A pizza however is completely made to order on demand and if there's a mistake the components are nonrecoverable waste.
With Apple's custom SoC, they're designing a custom circuit however that specification is sent to someone else to manufacture. At it's core, it's not unlike ordering a pizza of astronomically greater complexity. So what makes a custom pizza just an order and not a make? Is it the relative simplicity/complexity of the task?
If I enlist a factory in China to manufacture custom mouse pads based on my exact specifications, did I make a mouse pad or just order it? Does it matter if the mouse pads are just press cut fabric backed neoprene in various colors and shapes?
Glasses are somewhere between an Ikea Sofa and a Pizza in terms of modularity. The lenses and frames are off the shelf but once cut the lenses are spent if an error is made. Glasses however have much more exacting specifications than a pizza or a Sofa.
Re: Making My Own Glasses
#108Re: Making My Own Glasses
#109Earlier quoted context omitted.
I recently (in US) asked for it, and was given a hand written sticky, begrudgingly after asking why you need it. But once asked again, no further objection.
Your PD isn’t part of the prescription. But the prescription itself must be provided to you by law in the US.
For anyone near a Warby Parker, they'll happily measure your PD in about 30 seconds. Measurements can vary slightly so you might want to do it a few times and average them.
Re: Making My Own Glasses
#110Fascinating hacker story in an unexpected domain. Thank you! A side note about "getting your numbers"... The author remarks, "she’s not happy to share the measurements with me as she fears I’ll run off and get my glasses made online". This will obviously vary by jurisdiction but what the author describes may be illegal in some places. e.g. where I live, there is a law since 2010 requiring opticians and optometrists "…
Not sure about legality but here in the UK you will find opticians will give you your prescription, but often exclude the pupil distance measurement (I think) which a lot of the online stores require. I think you can ask for it, but they will only give it begrudgingly.
That's cause PD is measured by the optician separately when you're ordering your glasses, not by the optometrist or opthalmologist who writes the prescription.
In other words, it's not part of the prescription, it's instead part of the glasses fitting process.
A non-eye related example would be if your doctor prescribed you a brace and the person at the medical supply store measured you to find out which size you need.