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How I clean my glasses

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Re: How I clean my glasses

#231

Post by conductr »

nunez wrote: post #196
conductr wrote: post #143

Earlier quoted context omitted.

Lenses are much cheaper to manufacture than most people realize. Most of the coatings and upgrades are 95%+ profit with very little cost. An interesting thing I learned in that industry, the uncut "puck" of plastic/material is usually cut to your prescription via an CNC style machine. The cut instructions are essentially a pre-built CAD file based on your prescription/measurements. A significant cost of the process i…

That sounds about right. I remember having gone to an optometrists office some time back and they were able to cut lenses right there and have glasses ready in an hour. I was amazed and couldn't understand why everyone couldn't do this. Sunglasses are the worst. They cost basically nothing to make but the profit margin is Inf% b/c of branding. A $20 (at most) pair of non-name sunglasses instantly becomes a $700 pair…

The locally made lenses still exists but it's becoming very rare. When I was a kid my parents went to a one-hour place, that made them on the spot. It's still possible but not economical. Not that they passed the savings to the consumer of course. Gotta love economies of scale.

If forgot to mention sales commissions as I was talking about cost of goods. But a variable compensation for the sales person, is a lot of your cost if you are in a retail setting. Believe it or not, your optometrists gets paid commission too (if an employee) as does the person at the desk. It's a sales heavy business. Buy eyedrops, buy lens cleaner, buy here - we really don't want you to walk out the door with your prescription! We have a metric called "capture rate" that our commission is attached to!!

It's not too bad but was a surprise to learn it's much more retail than medical (as a business). I think in most the world it's not even necessary to see a doctor to get glasses, like in the US. I usually leave and buy somewhere else because my doctor just has a crappy selection of frames, every single time, he gives me the prescription when I ask. Then I have to ask for the pupillary distance and he acts like he doesn't know what that is. "Why do you need that?" Because if I buy online they'll ask, "Oh yeah, I can take that measurement".

Re: How I clean my glasses

#232

Post by twawaaay »

pcthrowaway wrote: post #230
twawaaay wrote: post #158

Earlier quoted context omitted.

That's bad. You don't want to dry it, you want to remove the water BEFORE it has a chance to dry out. If you just dry it out, the mineral residue from water will be left on your glasses. More than that, mineral crystals are incredibly abrasive so next time you try to clean the glasses they will be abrading and destroying your perfect glass surface.

The author of the submission mentions they use distilled water , presumably for this reason

For starters, I have responded to a comment from a user, not to the submission.

And second, using distilled water to clean your glasses must be strong contender for least practical glasses cleaning technique.

Blow the water off

vs

Find that jug of distilled water (make sure there is one at work and at your parents in law), then rinse with it (you can do it, hold the jug in one hand and the glasses in the other, don't use all the water), then use the hair dryer on cold to dry your glasses.

--

If you need distilled water and hair dryer to do it the result will be permanently dirty glasses, not clean ones.

Re: How I clean my glasses

#233

Post by rosmax_1337 »

frogulis wrote: post #228
andrelaszlo wrote: post #95

Earlier quoted context omitted.

I asked the optician how they clean glasses: - Wash with cold water. Warm or hot water might ruin the coating. (Our water comes supercooled right out of the tap in the winter,so in order to not have my hands instantly frozen into a solid block of ice I go for 15—20 degrees or so.) - Use a drop of mild dish soap without ammonia. - Dry them with a soft clean cloth (they use microfiber I think, I just use a random soft…

> Our water comes supercooled right out of the tap in the winter I'm from a place that never really gets below freezing, so I have to ask. Is this serious? If so, that's fascinating. When you turn the tap on, does the water instantly turn to slush on the way out? Does it come out at full speed or sluggishly?

It is serious but in hyperbole. The water is probably near freezing, but not below. Frozen pipes are a big problem in cold regions, they expand and burst, so measures are taken to insulate and keep the pipes warm. Depending on the piping though, sometimes the only resort is to completely drain the pipes during winter and not have any running water for that part of the year. (Common in cottages rather than real homes)

Re: How I clean my glasses

#234

Post by a2tech »

frogulis wrote: post #228
andrelaszlo wrote: post #95

Earlier quoted context omitted.

I asked the optician how they clean glasses: - Wash with cold water. Warm or hot water might ruin the coating. (Our water comes supercooled right out of the tap in the winter,so in order to not have my hands instantly frozen into a solid block of ice I go for 15—20 degrees or so.) - Use a drop of mild dish soap without ammonia. - Dry them with a soft clean cloth (they use microfiber I think, I just use a random soft…

> Our water comes supercooled right out of the tap in the winter I'm from a place that never really gets below freezing, so I have to ask. Is this serious? If so, that's fascinating. When you turn the tap on, does the water instantly turn to slush on the way out? Does it come out at full speed or sluggishly?

I believe they were exaggerating a bit. Water pipes are typically buried deep enough in the ground that the water gets very cold but not frozen. The pressure in water lines isn't high enough to really drop the freezing point of the water to an appreciable amount.

Re: How I clean my glasses

#235

Post by frosted-flakes »

sgt wrote: post #216
frosted-flakes wrote: post #140

Earlier quoted context omitted.

I can definitely get thinner lenses using a higher-index material, but I selected this lens material specifically because it has a higher Abbe number and thus has less chromatic aberrations. The thickness doesn't bother me, but chromatic aberrations do, a lot. I cannot tolerate the excessive colour fringing high-index lenses have, and while contact lenses don't have this problem I dislike those even more. I have lens…

The chromatic aberrations are there but I think you just need to get used to them. Alternative is heavy glasses.

That's not true. My glasses are super light and the thickness is not a concern whatsoever. I can shake my head back and forth with my head down and they don't move at all. And for the past decade since my Rx got particularly bad I have always found the aberrations annoying, so no, I won't "just get used to them".

I can't stand chromatic aberrations because they make everything outside of the centre of the lens blurry. This worsens my tendency for one eye or the other to wander if I'm trying to focus on something just at the edge of reading distance (road signs or restaurant menus, for example) and makes driving at night in the rain difficult. My current glasses have an acceptable amount of abberations, but my previous set was horrible.

I really should be wearing contacts and I've tried them several times, but I generally find them very uncomfortable and I've always hated how they take away my perfect close-up vision.

Re: How I clean my glasses

#236

Post by oezi »

jackspratts wrote: post #66

Hotest water you can stand. Blast copious amount over lenses, both sides. This removes some grease and large grit. Put several drops of detergent on finger tip and rub onto thumb tip. Using thumb and finger coat detergent onto both sides of both lenses then rub gently. A few seconds is all you need. This removes all remaining oils and suspends any remaining grit preventing friction scratches during cleaning. Rinse le…

I would strongly advise against paper towels. With bad luck these contain small splinters of wood that might be just as sturdy enough to cause small scratches. Happened to me on a pair that I had just worn for 6 weeks.

Re: How I clean my glasses

#237

Post by sbierwagen »

adzm wrote: post #101
tecleandor wrote: post #77

Earlier quoted context omitted.

I have a Zenni pair, I think they are 1.74 and around -6 correction in each eye. They are really cheap compared to other places, but they have very high chromatic aberration on the sides and I don't thing they are perfectly centered. I think it's something that's more noticeable when you need relatively high power lenses.

It's good to have a high quality pair from a local shop so you have something to compare Zenni or other online shops to. YMMV of course, but I've had good experiences with Zenni, and only had one pair out of dozens for my family that had issues (seemed to be uncentered or had the PD incorrect), and that was over 5 years ago. It's nice being able to grab a cheap pair of glasses for activities where there is a high pro…

>so you have something to compare Zenni or other online shops to

That's for sure. I bought a pair from 38dollarglasses.com and skipped the antireflective coating option. As it turns out, if you've worn glasses with AR coatings all your life, plain lenses are really, really surprisingly annoying.

Re: How I clean my glasses

#238

Post by otikik »

I got lasik eye surgery and got perfect vision in 20 minutes, more than 15 years ago. Best decision ever (don’t skimp on this, go to the best professional you can afford)

Re: How I clean my glasses

#239

Post by superkuh »

tecleandor wrote: post #77
jefftk wrote: post #65

Earlier quoted context omitted.

At least in the US that would be much cheaper: I can get high index (1.74) lenses for +$75: https://www.zennioptical.com/glasses-lenses (so the overall glasses are ~$100)

I have a Zenni pair, I think they are 1.74 and around -6 correction in each eye. They are really cheap compared to other places, but they have very high chromatic aberration on the sides and I don't thing they are perfectly centered. I think it's something that's more noticeable when you need relatively high power lenses.

Yep. Once your lenses get above -6 diopter or so it starts to become a serious concern. By -10 diopter it's the driving choice in lens material and design.

At -10.5, -11 I always get relatively low refractive index (~1.5) CR-39 based lenses because it's Abbe number is 60. This means I can still read, say, street signs or flanking computer monitors out of the corner of my eye despite the light going through literally >1 cm of material.

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