We get slightly nearsighted at night, corneal aberrations, and stars
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- Опубліковано 14 бер 2023
- A quest that began with looking through my wife's glasses at the alarm clock, and noticing something odd about the blurries. This got me down the rabbit hole about optical aberrations in the cornea, night myopia, and possibly why we think of stars as stars.
Now I'm in a circle of confusion but still impressed.
A smaller image makes it less obvious. 😉 Try watching on your phone. 😳
I had to look that one up, I love it when nerds get to name phenomenon lol
I’m nearsighted. Growing up, my eye doctor would dim the lights in the room before testing my vision, projecting the eye chart on the dark wall. I switched eye doctors when he retired, and the new doctor didn’t dim the lights. My vision with the new doctor magically “improved” and my prescription was about 1 diopter weaker. This probably explains why.
More light means your pupils get smaller, which means your focus being off matters a bit less. But that alone shouldn't account for a whole diopter change! What I'm talking about only applies for when it's too dark to see 20/20 even at the best of times.
When I get an eye exam at the DMV, I stare at the light a few seconds. I no longer have an eyeglass requirement on my driver's license. (Iris closes down, bringing things into focus)
Actually, from a young age I would run into doors because the ligths shouldn't have dimmed.... Took me 10 years and 2 eye doctors before we had that one figured out. Mye eye sight is like -5 at night and -1.5 during the day... pretty severe.
And by George, the accompanying headaches from the terrible glasses....
I remember as a kid asking why people draw stars as they do - because the real ones just look like tiny dots. I only saw a point like object, that if i had to guess its shape, would be round. Never really occurred to me until this video that people might actually see the stars as 'star' shaped objects. Its funny how we see the world differently and don't realise.
mist 5 year olds and younger are a little farsighted. which means you would probably have focused slightly differently on them and seen them more like dots.
The irony of using precision optical equipment alongside a literal wet sandwich bag is amazing. Also that little tidbit about the shape of stars is great, one of those "oh, _that's_ why it looks like that" moments!
I wasn't using any precision optical equipment. The only thing that would even qualify as optical equipment was the -2 cylinder lens I used briefly
If we use the "shitty lens".... Love it! Can't wait to read a white paper or some kind or research paper that includes such eloquently defined components .
Oh Mathias, your observations are priceless. I don’t know if you realize how funny you are! I’m having visions of you in the middle of the night wearing Rachel’s glasses because of some random thought that drifted through your mind while you were asleep. I have thoughts just before I go to sleep but it’s usually not anything intelligent. More like cartoonish in my case. Keep up the great work!
Man I love this channel. So many neat things to learn that I otherwise wouldn't even think about. Thanks Matthias!
One confounding factor that you didn't delve into is that as the iris dilates, the depth of field narrows; if someone were marginally nearsighted, it would be more apparent with dilated irises even if the point of focus had not changed.
True. 3 of the 4 friends I tested this are adults wearing glasses, so I assume nearsightedness was already corrected for.
I’ve worn glasses for my severe nearsightedness almost all of my life. When my glasses are off, if I look through a tiny hole, I can see with some detail. This kind of explains this.
Pinhole effect. Optometrists will sometimes have patients look thru a pinhole to figure out how well you can see fully corrected.
Yeah, that's actually an old trick my grandpa taught me if you lose your glasses: poke some holes in a piece of paper and hold those in front of your eyes too look around until you find them.
Just got Lasik and wish I took a mental note of "before" control test so I could be confident if/when my night vision performance gets back to normal. Granted I don't have a focussing kit but love the coincidental timing of this video
i had lasik done 20 years ago, now hitting 48 and in the last 2 years my night vision has tanked really badly, still not bad during good light but interesting to find the reason here :)
I like when people engage their brain to wonder and think critically.
Thanks for taking the time to share this very interesting observation. 🙂
Dr. Matthias 👓 I love it 💕. You're too damn smart for me 🤣🤦♂️
From self taught woodworker to self taught optometrist. Impressive, what's next?
there would be more videos on this topic, if only more people watched them!
Everyone watch this video 2 or 3 times on each of your devices so he makes more of them!
@@matthiasrandomstuff2221
Ich war etwas zurückhaltend diese Videos zu gucken als ich die neuen thumbnails und das 1. april video gesehen habe, ich glaube einfach weil es nicht das gleiche wie sonst ist und die natürliche abneigung gegen neues reingekickt hat. Jetzt wo ich es gesehen habe schau ich mir auch gern weiteres dazu an, war eine schöne mischung aus Geschichtenerzählung und Physik.
A few years back I noticed while hunting, before sunrise I could see better without my glasses. At the time my prescription was +0.5
I remember thinking at the time that it must have something to do with "depth of field" and larger aperture.
Fascinating stuff, Matthias! 😃
Stay safe there with your family! 🖖😊
I love your use of the SSB lens. Very interesting! Great science video.
BTW... You should work as a freaking scientist, Matthias. The world needs people like you.
Who says he isn't? I say he is more of a scientist than most. People with such UA-cam channels are even though they don't make academic studies. The videos are the proof.
Thank you for sharing that rabbit hole
This was excellent! My sisters family was just at Science North. This is a perfect experiment for that sort of venue. I’ll be showing my 8 yo this video.
You blew my mind! I ❤️ this stuff!
If we dive deeper into how our eyes see things based on light and its own structure, we might even be able to solve more puzzles like some gods have a circle behind their head, could it be circle of confusion?
Also this would explain ghosts and magic, this star discovery is amazing, If the person who brought stars into academics had good sights we would have gotten away with just drawing dots instead of two triangles, but we wouldn't have twinkle twinkle little stars then, so it was a happy accident
This explains why I can see the clock at night. My bedside clock projects the time on the ceiling and I wear varifocal spectacles.
if it projects to the ceiling, it will just be really big, so you don't need glasses to see somethign that big
Super amusing, food for thought indeed!
Interesting video - I had my eyes laser corrected 22 years ago - in my case the surgeon corrected the cornea beyoond the edge of the pupil so I have been free of night-time streaks and twinkles ever since. - best decision ever. zero complains
That is some top notch nerding out. I love it.
Some more food for thought regarding vision: I had cataracts surgery last year, right eye on January, left eye on May. After surgery you see everything mostly pink because of inflammation but as it subsides you return to your normal vision and that's when you realize everything is much colder than before. Turns out the eye with myopia (and maybe eyes in general) get a yellowish tint with time, however since it's the only "white" you see you never realize. Once I had the surgery it was amazing how the white I thought was white was actually yellowish, as if warm white, and the new white was much bluish as in cold white. Until you have that surgery you would never realize that what you think is white is actually not white.
It kind of reminded me of this book I read, "Through the language glass" by Guy Deutscher where he mentions greek called the sea "wine-dark" not because they mixed wine with something to make it blue but because they actually saw them as the same color until someone much later named blue and purple. Or that the old America aborigens could not process the Spanish ships traveling the sea with the limited knowledge they had so they just ignored them, made them effectively invisible in their heads (quote which I can't source at this moment).
The color thing is odd. If you put on slightly tinted glasses, your eyes quickly adjust and white seems white again. I had an odd experience years ago. I went into an outhouse at a fair, it had a green transparent corrugated roof. there was a hole in the sdie of the outhose, and I could see the sky looke pink. I thought something pink covered the hole, but putting my finger thu it, there was no such thing. My eyes had adjusted to the greenish light, so suddenly the natural blue light of the sky thry the hole now looked pink!
I was under my car working with a trouble light when I realized my two eyes perceive colour slightly differently. Alternately closing one eye then the other revealed the rust under there was slightly redder through my right eye. No surgery or other mods.
I had a similar kind of surgery only in my left eye. I also notice the difference in color perception. Even since my surgery was already 7 years ago my brain has still not fully adopted. However the effect has become less strong.
My uncle had the surgery he says the blues are much more intense.
@@ColCurtis I had a cataract removed from my right eye and I can see UV much better in my right eye than in my left. If you shine one of those UV flashlights on the wall the beam much wider when looking through my right eye compared to my left. I think it's because the cornea naturally filtered some of the harmful UV rays.
Love the star shape extension. Tasty thoughts indeed
That star thing really got me 🤯
I remember hearing about the idea of lens aberrations as causing the star shape to be interpreted by our minds.
Very good Mr. Matthias Fourhundredeyes
Fascinating! Thanks!! 🙂
The breadth of your interests is quite a wonder.
Holy smokes! I can’t believe you just perfectly explained why I see pinpoint lights at night with the star burst effect around them. I thought there was something wrong with me lol
undercorrected nearsightedness makes that effect bigger
Extremely interesting. 🤜🤛👍👍
My optician told me about getting more nearsighted at night but this made me understand it a lot better! I'm nearsighted and I prefer about -0.5 more than my tests show, even in bright daylight, as I find the standard prescription doesn't let me focus to true infinity. Not sure if it's some defect in my focusing mechanism, or as my optician suggests that my retinas could be higher resolution than the norm, but I thought I'd share :)
optometrists say young myopes love their minus. but they are reluctant to prescribe any more minus than absolutely necessary because it may accelerate the progression of myopia.
Same here. When I first got glasses, I could see the chromatic aberration and lens flare. The optician thought I was crazy! I went to contacts soon after.
“Shitty sandwich bag lens”. This may be a brand new phrase.
Being into optics because of photography, this is very fun to watch! Lenses "suffer" from all that the human eye can go through, and I'd call smaller iris size : "deeper depth of field" (which explains better focus, e.g. reasons you already mentioned). Only the scale changes (same goes for large format cameras VS, say, 35mm).
Anyhow. It was also fun to see you come up with your own prescription for glasses (potentially)! [from another video]
You still should have a proper eye doctor examination for other hard to detect problems (cataracts, glaucoma, etc.)
Well, I ordered glasses using those numbers (wearing them now). Will go see the optometrist once it's been 2 years, so my wife's work benifits will cover it.
Brilliant!
Very interesting, also you're getting quite good at flipping those lens flippers.
I just had a thought last night wondering if eyes work like cameras, where having a smaller aperture means a wider range of focus, and therefore being in the dark means your focus range is worse and can make seeing things harder.
this video popping up in my watch later today is a neat coincidence and an interesting watch
Nailed it right at the end
Very interesting.
This seems vaguely similar to the over refraction method used to treat my keratoconus (over refraction and 1500$ scleral lens) thanks for the demo
I've been following you for a while now and I'm surprised that you just picked up my bachelor topic for a video. Actually there are 3 processes that lead to this night myopia.
1. as already mentioned, spherical aberration leads to a defocus of about +0.2D.
2. when it is darker, we use not only the cones, but rods and cones (mesopic vision). This shifts the maximum sensitivity of the retina towards the shorter wavelengths. Since shorter wavelengths are more strongly refracted (dispersion), the subjective refraction is more negative to compensate. This longitudinal chromatic aberration results in an additional +0.2 dpt.
For this reason, blue dots are refracted differently in the dark than red dots.
3. resting accommodation without any stimulus is about +1D in most adults. Even to weaker stimuli, the eye responds with "overaccommodation" or resting accommodation. Stronger stimuli, such as distant car headlights, immediately reduce this effect. Depending on the illumination, this effect is between +0.5 and +2D in complete darkness.
You mean to say our focus muscles work in absence of light, but as soon as there is light, they relax a bit? My current thinking is, due to spherical aberrations, the eyes apply a substantial image sharpening effect and ignore a lot of flare caused by aberrations mostly. But when light levers are very low, the signal isn't strong or clean enough to do a lot of processing, so this breaks down in very low light. Personally, I can't accomodtate much any more - maybe 1/4 diopter. So I woudl think the focus acoomodation part isn't a significant contributor.
@@matthiasrandomstuff2221 that’s exactly what is happening.
Retinal image processing is also better for cones than it is for the rods. So under low light conditions with more rod-sensitivity the perceived Images get a lot worse.
A suggestion:
You can try what is your dominant eye and correct it for far distance. The other eye you can correct with (your prescription+1D) actually the brain is very capable of making a good viewing experience out of this.
You can tell what your dominant eye is by covering up a corner in the room with your thumb, both eyes open. When you then close one eye and the corner is still covered the open eye is dominant. If not the closed eye is dominant.
I don't think this has anything to do with your experiment but...............when I had Laser surgery back in 1996 It changed me from being near sighted to being far sighted, and at the time I didn't even know that could be possible. Ever since I've needed reading glasses, what a pain, but I could drive without my contact lenses after the surgery. You're always giving us something to think about. Thanks.
at my age, I would be happy to be slightly nearsighted, so I wouldn’t need glasses for most of what I do. I don’t even drive most days.
After your last video on the subject I ordered a set of trial lenses and worked out my prescription. My left eye is so bad that my brain mostly ignores it except for the peripheral vision and I was always curious whether it was even worth having a prescription for that eye. I suppose I could have just taken the lens out. The website I ordered from wouldn't even let me order progressive lenses with such a difference between the eyes of what my approximately correct prescription would be anyway. I can now also say for sure that there is no point in trying to correct for astigmatism in that eye. I can't tell you how much time I have spent over the years looking at two different but equally bad eye charts and having to pick between them for no benefit. Anyways it had gotten to the point where I was using the computer and reading with my glasses off as I couldn't focus close enough with them on and I would wear a magnifying headband in the shop. I shouldn't have put off getting the progressive lens for so long.
I ordered bifocals, hated them. So now I just wear a compromise most of the time. About 20/30 distance, but the stuff in my hands isn't terribly blurry.
@@matthiasrandomstuff2221 My dad said that progressive lenses were much better than bifocals so I went straight to that. They do take a little getting used to but after a week the only thing that still bothered me is walking down stairs. Can't see anything! Probably a death trap with young kids.
Very cool I have. Noticed people that see things differently than I do
For example the headlights on her car see sees each light projected by the car but I only saw one both where same shade as far as I could tell she is night blind also
I thought for a minute Matthias was going to ask: "Which is better, this ..... or this, this ..... or this"
Circle of Confusion sounds like a nice addition to a Magic: The Gathering blue deck
Interesting. Very cool tumbnail by the way.
first time I overlaid two images for a thumbnail. had to use gimp, which I don’t know all that well. unfortunately, it fails to bring in the views.
I had laser eye surgery (and regretted it deeply). I used to see stars as clear round dots with no starburst effect. Now, with my messed up corneas, there are big starbursts, along with a halo and coma shape........btw I still need glasses. - NEVER GET CONNED INTO HAVING LASER EYE SURGERY.
Look into RGP Lenses. Hard contact lenses have a tear resevoir behind the lens that will fill the little dimples in you cornea. its hard to get them fitted nicely in north america since this is not a common approach there. Here in Germany this is the routine lens for post lasik.
@@thefimo4505 You are referring to scleral lenses. Unfortunately it did not work for me as my post surgery eyes are too lacking in lubrication. 90% of people who attempt scleral lenses are intolerant of them.
A long time ago I worked at a manufacturer of intraocular lenses and they were aspherical to reduce aberrations. Some of them even had two focal points so you could see kind of close up and kind of far away. Think of it as a small lens in front of a large lens concentrically. You get some fuzz from the other lens being misfocused at each focal point, but you don't necessarily need glasses for far and near vision. The artificial lenses have zero accommodation (or did have, maybe the state of the art has improved) so you would 100% need reading glasses before.
yes, I find that fascinating. just rely on our brains to clean up the mess and make the best of it.
Nice.
I have astigmatism in one eye, corrected with lazer surgery. Could I have saved some money with a couple of sandwich bags? Love your curiosity, and sharing with us.
What we should do is to polarize light in such a way that all windshields blocked all light except for light coming from our own cars. Heck, house windows could take advantage to prevent car lights from contaminating indoor lights.
Neat idea. yes, we could have all windshields horizontally polarized, and all headlights vertically. Direct headlights wouldn't show, but light bounced off something from headlight loses its polarization, and does show. Only thing is, we wouldn't want to entirely block seeing headlights directly, that could be bad!
Huygens Optics is a good channel for this sort of stuff.
Spherical aberrations get really bad if you get Lasik surgery or ortho-k lenses. The treated area of the lasik can't be as big as your iris at night so even if the middle of your eye is good, you'll have a huge halo around any light source from light around the edges.
Prk surgery has a larger treatment area but has terrible recovery, like 3-5 years
That's not so much spherical aberrations but too small a corrected area. Problem is, the depth they have to blast is a function of diameter squared, so to cover the full pupil area, they'd have to blast away too much cornea and it would be too thin
Pupil or Iris - Iris would be a huge area...!
@@thefimo4505 certainly, I meant pupil.
This is interesting.
This must be why the dilation eye drops at the optometrist causes things to be blurrier
@DGlaucomflecken just found his newest character - The Optometrist! Crossover episode!
You could try looking at a Siemens star without glasses and drawing the shape where the contrast inverts. This would give a you a bit different information than the diffraction pattern of a point light.
Love it. Testing the new cussing adjustments on the ad algorithm. 😂
at night you could run into more trouble with light sources beeing monochromatic (-ish), for example blue scenes look blurred whereas reds don‘t. But that‘s due to chromatic abberation.
I’m quite surprised the eye doesn’t have an aspherical type lens. Being into photography since the film days that was very interesting.
well, its probably neither exactly spherical nor ideal
Both the cornea and the natural crystalline lens of the eye are aspherical
What I really meant there is that I was surprised they aren’t ideal. Though I guess if you look around in the world of camera lenses there is no amount of money you can throw down for any hand shaped glass that doesn’t have some compromise. Could be more of an issue with indexes of refraction and other physical limitations that compromise quality the more you bend light.
Its true that the Cornea induces ruffla 0.28µm SA (Zernike) But the lens compensates for most of this.
Can you do a video on solvents and plastics? I was watching a video of someone cleaning a battery terminal and they didn't use alcohol. They used one of the many contact cleaners. So naybe a nice comparison of name brand Contact Cleaners, rubbing alchohol, distilled water, and vinegear on metals and common plastic types. Mostly nickle plated items, but other metals work too if it seems necessary.
I’ve noticed a similar problem with stargazing as I get older. Apparently it’s possible to get tested for stargazing prescriptions for astronomers. Infinity focused eye glasses I guess.
Perhaps slightly more minus. Optomietrists optimize for vision at 20', which is 1/6th of a diopter short of infinity. So just adding one stop (1/4 diopter) more minus would be ideal for infinity. Also, a lot of optometrists won't go for maximum sharpness but good sharpness with the least amount of negative as possible. It's all about avoiding "over minusing" as they call it.
@@matthiasrandomstuff2221 That explains my new prescription! My old doctor retired, and the new one took me down .5 a diopter. It took a week to really adjust!
Actually this is were the night myopia was first described. Astronomers realized that their Telescope was not in focus by day and they would need more minus at night.
Looks like you need to publish a scholarly paper-- Spherical Aberration in Human Lens and the Traditional Star Shape.
Another aspect that might have a thing to do with this:
Receptors for colour-vision are in the center/focal point of the retina, the receptors for monochrome vision are located in a circle around that.
Which - as far as I understand - is the reason why you don't see colours when its dark enough, and why the vision is a bit blurry.
You might even know the german word "Morgengrauen" - daybreak or "morning-greying" for a rough literal translation, because everything is black and white then.
Very interesting topic.
the Color receptors just aren’t as sensitive. the highest res part of the retina, the fovea, is all Color receptors. those stop working at very low light, so visual acuity goes way down.
@@matthiasrandomstuff2221 true, thats something rather important I forgot to include
Genius
Your sandwich bag with water is a good analogue to the human eye since you can squish it around. I can improve my vision by putting my index finger on the corner of my eye and pulling the skin towards the ear. Obviously it's not as good as glasses, but if I ever don't have glasses and need to see something clearer I know I can do that.
I discovered the same thing too when I first got glasses. Poknig my pinky into the eyelid in the lower left of my left eye warped the eyeball a little to cancel the astigmatism. Not a trick I ever used much, and probably for the better!
That’s exactly why people with bad eyesight squint! It changes the shape of your eye slightly. It also gives you headaches, though.
Circle of Confusion would be a great band name
Do you think glasses affect your ability to line things up by eye? I’ve been attaching planks to a stud wall with screws about 10” apart and when I stand back and look at it the line is not straight! I swear I used to be good at finding the center! Is it the magnification? The astigmatism correction? I started using a torpedo level to mark my screws before I got very far up the wall. Maybe this is related to “I make more mistakes than I used too” and not optics. Either way, aging is disappointing
The points (number, spacing, length, etc) on stars being the result of human eyes being less than perfect is plainly obvious from a very early age for those of us who have never had remotely the same glasses prescription in both eyes. And probably anybody with astigmatism since the star shape is heavily dependent on how horizontal their glasses are, rotating that lens just a tiny bit makes a big difference.
the last part about stars is true. you learn those things on Fourier optics textbooks
well, this is different from Fourier diffeaction. Fourier type diffraction makes the points on the stars with a lot of cameras.
I noticed a strange thing at night, looking at an illuminated sign of a shop composed of red and blue words. The red lights look really sharp while the blue ones look very blurry. 🤔
Blue is always hard to focus
I have an eye disease called Keratoconus mostly in my left eye. The big letter E just looks like a black spot with out any correction. With both contacts and glasses I can kind of see with it. I do not need glasses nor contacts with my right eye. I can see movement with my left eye which helps driving. When I push the buttons on the phone I sometimes push the neighbor button. Just for your information my eye is like and island nice and round that has been turned on it's side. Just like the island everything shifts. I no longer look through the center so that's the problem. For the last few years my Doctor say they will have cornea transplant in about 10 years. What I see from your video, a lot of what you are seeing looks like what I see only for me more so. I know I don't need to say this, but please have your doctor check your eyes. I truly mean you well. BTW in 10 years I will be 78.
I have been fascinated with optical aberrations in the eye. But I don't think what I'm seeing is worse than usual. I see quite ok despite the aberrations, and some spherical aberrations are normal. I think the eyes relay a lot on the brain correcting for a lot of bad optics. Other than age related farsightendess, there hasn't been a whole lot of changes in my eyesight, so I'm pretty sure I don't have keratoconus. Will see the optometrist again once it's been 2 years since my last visit, so my wife's work benifits will cover the cost. Researching all this, I have become fairly knowledgeable on the topic, so I'm pretty sure I'd recognize symptoms of something drastic like keratoconus. Glaucoma not so much though.
@@matthiasrandomstuff2221 Two things. 1) I didn't mean to imply that you have what I do. I just met keep watch on those eyes, you can't get new ones. 2) My old eye doctor took about 5 years before he told me I needed to see someone else. He would spend 20 min looking at my eyes longer than he did my wife or daughter. I know he did the best he could. If you do have it, you may not know for a few years. I knew my left eye was not as good as my right, I just didn't know it was that bad. BTW when the school told my mom I needed glasses she took me. After they ordered them she ask me why didn't I tell her I could not see good. I told her I didn't know I could not see good. All the trees now had leaves. A lot of water has gone under the bridge. I am happy with what God has taken me through. Thanks.
This video made me more aware of my actual eyes, and this made me uncomfortable. 5 Stars as usual.
I am mildly nearsighted, but the night sky is a no go. I can see some stars, but telescopes are a no go for me. Next time I will try a stronger prescription for night time, this all makes a lot of sense.
try some -1 myopia glasses off of aliexpress and hold those in front to see if it helps any first
The limit of acuity to the human optics appears to be 20/8 with few cases of visual prodigies excelling past that, but I'm skeptical of 20/5 being achievable. I would say in order for someone to see a star as a bright sharp pinhole of light, one would have to at least be 20/10 or better. Looking through perfect optics at a full moon, I've noticed a very bright razor sharp ring outlining the moon (the edge is really defined against the black night sky) if I add even as little as +0.50D, that sharp edge seems to ghost out into the surroundings. I imagine most people do not see the night sky as vibrant as they think. After the age of 20, having zero optical aberrations is almost impossible, especially in these times. I always wonder how eagles would see the night sky with their 20/2 vision...I bet they could see details inside those dark craters on the moon and the sky is obviously filled with a lot more stars.
this whole business of optical abberations, focus and image processing in the eye is fascinating and complex. google “blur adaptation” for another angle on it. enough material for many more videos but I’m not expert enough to say anything really conclusive.
@@matthiasrandomstuff2221 At one time I was wearing a +4.00D for about an hour each day and noticed significant vision improvement after a month of doing so. I believe the immense change between going from seeing somewhat clearly to inducing significant blur, created positive stimuli within the eye. Wearing the plus permanently would be counterproductive to producing stimuli. Even after wearing the +4.00 for one hour, slight resolution in VA can be noticed. As of today I've improved my eyesight by 3 diopters and can see clearer than ever.
Looking forward to the next experiment where you make a pair of glasses out of ziplock bags... :D
I have never seen this effect myself (still got relatively good eyes maybe) but I have noticed chromatic aberration when looking at certain red and blue colors next to each other. Turns out its hard to sharply focus both at the same time.
You need a -0.75 diopter lens to test this with.
The dispersion leads to different refractive indexes for the two colors. This leads to different Focal points for red and blue light. Absolutely true.
I noticed that in certain car windscreens at night they can make your vision blurry when there is not enough light. Look out through you door with window down the the blur is gone. Anyone else notice this?
possibly your eyes end up focusing on the dirt on the windshield?
I wonder if different parts of the light spectrum are affected more than others due to the spherical aberration. I have trouble with blue light at night, not during the day and not other colors.
No need to wonder. It’s definitely the case. Different wavelengths of light refract differently in glass, which is why cheap lenses show lots of chromatic aberration around the edges of areas of high contrast.
👍
Yup I have glasses and the stars look like the last image
I wish I knew as much as this guy has forgot.
The "circle of confusion" is often referred to as "bokeh" by photographers.
Bokeh is actually referring to the pattern of unfocused light, caused by the circle of confusion.
😁👍
Minutephysics made a video about star shape/eye imperfections.
I gotta go find that
If you make the aperture very small you end up with a pin-hole type lens. You can get pin hole glasses. In theory (my weak and probably wrong theory) with enough light these glasses should work better than lenses.
to a limit. If the pinhole is too small, you run into diffraction limits. Look thru a 1 mm pinhole in daylight, won't be all that sharp.
Now we need some collab with Tarras who recently did a video about his laser eye surgery! Maybe we could fix his eye poking and flaring :P
nope. I would not be doing anything physical to anybody’s eyes
@@matthiasrandomstuff2221 I meant Taran Van Hemert - I don't mean anything physical but just playing with some of the lenses and other related stuff. He could give you some tips on video editing which is his specialty..
Can you create a video talking about THD, specifically how's that important running sensitive electronics on electric generator, thanks!🤓
I assume you mean thotal harmonic distortion, and that you are commenting on the wrong video. Harmonic distortion isn't a problem so long as it's not very high orders. Harmonic distortion is more of an issue for induction motors.
Aberrations in the cornea. Just one more thing to worry about.
Not really. it is what it is. What's amazing is that it works as well as it does.
next episode Matthias open an Optometrist office.
(i would go there!)
that would be illegal. and only fun for a while. also, though we think of them as mostly measuring for glasses prescriptions, they look for a lot more than that.
@@matthiasrandomstuff2221 on another note: i dont know if it is the same where you live, but here in Quebec they are purposefully NOT measuring your PD (pupilary distance) until you buy a pair of glasses from them and NOT writing it on your prescription. so as to prevent people from buying their glasses online. the province passed a law that force them to give your prescription if you ask for it, but still...
i personally started buying my glasses online when i discovered that it was basically the same thing the store was doing for a 500%+ markup. a normal pair is 20$ and a all-dressed sunglasses+mirror+polarized+prescription is 100$. you might already know of this, but please give it a try!
I have mild short sightedness (-.25) but pretty bad astigmatism (-.75). I hate wearing glasses because they distort my view. When walking I feel like am about 2 feet shorter. Wonder if you can demonstrate what is happening there.
When I first got glasses 31 years ago, with some astigmatism in both eyes at about a diagonal, both eyes, symmetric. It seemed like everything was leaning towards me. But that effect passed after a few days, even with only wearing them occasionally.
Here, I have a mind bender for you.
Do you know the function of chlorophyll and how it works?
You know the function of an eye and how it works.
Do you think the two are genetically related? Possible for a shared genetic string in there?
Isn't it weird that in every cell their is a symbiotic relation between the mitochondria and and the rest of the cell with the mitochondria having its own DNA? I haven't looked it up lately but I wonder if chlorophyll is the same. Our bodies often treat the eye as its own unique system, many diseases will begin to attack the eye as a foreign invader to the body but mostly the body treats it also as a symbiotic system, it is beneficial to the body to protect it, so we can gather resources for the body as a whole, thus feeding and maintaining the eye.
The eye and chlorophyll both take light, turn it into a form of electrical energy that the body can then translate into something else. I just found it a weird relation between the two and thought you may enjoy thinking about it.
Have a good one.
Ive always said, if you need to see something better, add more light
So if I'm correct in my understanding, my take away from this is that a set of glasses between -1.00 and -2.00 would help give a clearer picture of the stars?
I'd say maybe -0.5. the -2 was with light much less bright than the stars.
I just watched one of your videos with headphones for the first time, and the sound of your voice drifts between left and right a LOT. I guess this has to do with the built in stereo mic of the camera. Anyway just wanted to mention it in case you are not aware.
The stereo mic on the new camra is much more stereo. I have to actually apply balance so thevolumes are the same.
My optician should do more woodworking 😮