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Medicine Space

Are Your Solar Eclipse Glasses Fake? (scientificamerican.com) 90

SonicSpike shares a report from Scientific American: A day after the American Astronomical Society (AAS) announced that there were no signs of unsafe eclipse glasses or other solar viewers on the market in early March, astronomer and science communicator Rick Fienberg received an alarming call. Fienberg is project manager of the AAS Solar Eclipse Task Force, which is busy preparing for the total eclipse over North America on April 8. He's the creator of a list of vetted solar filters and viewers that will protect wearers' eyes as they watch the moon move in front of the sun. When a solar eclipse last crossed a major swath of the U.S. in 2017, Fienberg and his team spotted some counterfeit glasses entering the marketplace -- imitations that distributors claimed were manufactured by vetted companies. Testing at accredited labs indicated that many counterfeits were actually safe to use, however. This led the task force to describe such eclipse glasses as "misleading" but not "dangerous" in a March 11 statement meant to reassure the public.

But then Fienberg's phone rang. The caller was "a guy who had bought thousands of eclipse glasses from a distributor who had been on our list at one point," Fienberg says. "Those glasses were not safe. They were no darker than ordinary sunglasses." Legitimate eclipse glasses are at least 1,000 times darker than the darkest sunglasses you can buy. Fienberg contacted Cangnan County Qiwei Craft, a Chinese factory that he knew manufactured safe glasses and had -- in the past -- sold them to the distributor in question. But this time, Fienberg says, factory representatives told him they hadn't sold to that distributor in a long while. "That's when we switched from being concerned about only counterfeits to being concerned about actual fakes," Fienberg says. The AAS does not have a confident estimate of how many fake or counterfeit glasses are for sale out there. And though Fienberg doesn't think this is a widespread problem, the situation is an "iceberg kind of concern," he says, because there are likely more examples than the ones he knows about. While counterfeit glasses may still be safe to use, completely fake glasses could put wearers in serious danger. [...]

While lab tests are the best way to determine whether glasses meet the ISO standard, Fienberg says there is a three-part test people can do at home if they're concerned their eclipse viewers aren't up to the task. First, put your glasses on indoors and look around. The only things you should be able to see are very bright lights, such as a halogen bulb or a smartphone flashlight. Then, if the glasses pass the indoor test, bring them outside -- but don't look at the sun just yet. Look around: it should be too dark to see distant hills, trees or even the ground. If that second test is passed, keep the glasses on and quickly glance at the sun. You should comfortably see a bright, sharp-edged round disk. If your glasses pass all three tests, they are probably safe to wear. Still, Fienberg points out that it's best to use them for only a few seconds every minute or so during the eclipse; this cautious approach is how they're intended to be used. And if you don't trust your glasses for April's celestial event, you could try to find a reliable pair in the next two decades. "You only have to wait 20 years for another really good eclipse year in the [United] States," Fienberg says.

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Are Your Solar Eclipse Glasses Fake?

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  • by Rei ( 128717 ) on Thursday April 04, 2024 @06:11AM (#64369218) Homepage

    * Designed for staring at intensely radiating plasmas
    * Who fakes a welding helmet?
    * Face well protected from freaking-out wildlife
    * As a general rule, if people see a person in a welding helmet staring at the sun, they leave that person alone.
    * Leaves you prepared for the inevitable post-apocalyptic future should Fenrir ultimately succeed in eating the sun this time.

    • Re:Welding helmets (Score:4, Informative)

      by Zarhan ( 415465 ) on Thursday April 04, 2024 @06:14AM (#64369222)

      Welding helmets work, but only if they are at least Shade 12 or darker.

      Or if you don't trust ready-made glasses, just grab a bit of mylar (e.g. https://www.amazon.com/Baader-... [amazon.com] ) and make your own.

      • Welding helmets work, but only if they are at least Shade 12 or darker.

        Or if you don't trust ready-made glasses, just grab a bit of mylar (e.g. https://www.amazon.com/Baader-... [amazon.com] ) and make your own.

        I just bought some shade 13 welding glass plate inserts for helmets. Cost me about $8 each. They work just fine without a helmet, we made cardboard glasses from them for fun with the kids and they can also just be attached/held to a smartphone for easy photography/videos.

        • I've done partial eclipse photography through welders glass, but the quality isn't nearly as good as through a thin solar filter.

          • I’ve found the image is pretty good quality, but the thickness means you see internal reflections of any really bright point light source. Still, I’d rather view through welding glass than film but for photography a thin filter is probably better.
            • but the thickness means you see internal reflections of any really bright point light source.

              Which totally ruined my "Bailey's Beads" shot of the 1999-08-11 eclipse. Which is why I got an ND5 (1 part in 10^5) and an ND2 filter a few years back in a stackable system. And I've not had an eclipse to photograph since. I managed to lash up a projection system when my step-daughter told me "there's meant to be a partial solar eclipse today" - and she didn't even bother to take her photos (of the projection, and

      • Most of my welding helmets are now auto-darkening LCD helmets. While they are adjustable in darkness up to ISO 15, I do not recommend using this style of helmet to view the sun. The reason is that will not always auto-darken when held up to the sun. They are designed to react to the change in light intensity given off by the arc, and they work fantastic for welding, and very reliably. But they won't always darken if just held up to the sun. Or they may darken, and then lighten again suddenly. Some helm

        • by ls671 ( 1122017 )

          Anyway, personally, I won't ever look at a Sun eclipse directly, don't matter what kind of protective glasses are available. Just not worth IMHO and the whole idea seem silly to me.

          • Perfectly safe to do it during totality, and even to use a telescope, or binoculars, since the sun is completely covered by the moon. Just be sure to put them away well before the end of totality. And it looks *amazing*. Even the best photos don't show the intricate detail and colours in the corona, nor how far away from the sun it spreads

        • Many auto darkening helmets also have a sensitivity adjustment. Mine will go dark even with a flashlight with the default settings. It will darken with the sun every time (even just looking in the general direction) unless you turn the sensitivity all the way down.

          • by tlhIngan ( 30335 )

            Many auto darkening helmets also have a sensitivity adjustment. Mine will go dark even with a flashlight with the default settings. It will darken with the sun every time (even just looking in the general direction) unless you turn the sensitivity all the way down.

            That's the problem - you don't want to accidentally bump the setting while you're looking at it.

            Most also let you choose the shade, and generally speaking, they usually only go up to 13, which is barely sufficient. It's also easy to bump the setti

        • I do not recommend using this style of helmet to view the sun. The reason is that will not always auto-darken when held up to the sun

          The glass and LCD material will still absorb the most-damaging emissions from the arc (or the Sun) passively, even before the LCD material and it's driving circuits decide it's time to go dark. So they'll protect the user from the worst effects of arc-welding (bright UV) and solar viewing (IR - heat zapping the retina) even if the "comfort" function of the darkening hasn't sw

    • by sinij ( 911942 )
      There are different types of welding - oxy (gas) and arc (electricity). Oxy welding glasses/helmet offer much less shielding as flame is not nearly as bright as arc. I am 100% certain Oxy glasses/helmet are not dark enough to look at the eclipse.
      • Gas welding has mostly fallen into disuse as arc welding devices have fallen in price and gotten more user friendly. You'd have to go out of your way to find gas welding glasses that can't be adjusted for arc welding.

    • Sure, with caveats. From the AAS: https://eclipse.aas.org/eye-sa... [aas.org]

      Are Welding Filters Safe for Solar Viewing?

      The ISO 12312-2 standard was based, in part, on decades of experience using welding filters for observing the Sun. A welding filter with a shade number of 12 or higher transmits a safely tiny percentage of the Sun's light across the spectrum, whether made of tempered glass or metal-coated polycarbonate. Most observers find the view through a shade 12 welding filter uncomfortably bright and the view through a shade 15 or higher-numbered welding filter unattractively dark. The "sweet spot" is shade 13 or 14, which best matches the view in purpose-made eclipse glasses and handheld solar viewers, except that the image is green rather than yellow-orange or white. Shade 13 and 14 welding filters are rarely stocked in welders' supply stores, though, so you'll probably have better luck finding them by shopping online. Two good sources of shade 14 welding filters are safesolarviewing.com and Phillips Safety Products.

      You should not use adjustable and/or auto-darkening welding helmets or similar products to view the Sun. Many don't go as dark as shade 13 or 14, and even those that do post a grave risk to your eyesight, either because you accidentally adjust them to an unsafe setting or because they don't auto-darken fast enough when you look at the Sun with them.

    • The standard for welding helmets and eclipse glasses are actually the same (shade 12 or darker). Many welding helmets have adjustable shade settings (some have a light shade for things like grinding, and you'd want a darker shade for a long bead on thicker material than a tack on thin material. .

    • Welding helmets work a treat if you don't care how they look to the people around you wearing eclipse glasses. You get tint choice with fixed shade lenses (I prefer cobalt blue for welding) which is just a comfort preference.

    • "Who fakes a welding helmet?"

      Someone who has identified an unqualified one-time market for welding helmets.

    • by tlhIngan ( 30335 )

      They're also relatively cheap - you don't want the trendy auto-darkening helmets (you don't want those = they may accidentally undarken, blinding you, or since they're variable shade, may be accidentally switched to a lower setting), which means you just need a cheaper helmet. And low end ones with a fixed shade are cheap.

      The filter glass itself is usually $5 or so, and they come in standard sizes.

      Hell, you probably can get one for free since a lot of welders provide useless handheld ones that work perfectl

  • Do you care? (Score:5, Interesting)

    by Mr. Dollar Ton ( 5495648 ) on Thursday April 04, 2024 @06:34AM (#64369254)

    Don't use glasses, use the simplest camera obscura - a piece of black paper with a pinhole in it. Project the image on a sheet of white paper. Enjoy.

    If you want more, you know where to go, to the surplus shed :)

    • by pjt33 ( 739471 )

      Or for a more elaborate version, get a large cardboard tube, cover one end with tracing paper and the other end with tinfoil, and poke a hole in the tinfoil. If the tinfoil is secured with an elastic band and under tension it should be possible to poke a really clean pinhole.

      • by sjames ( 1099 )

        My favorite is a cereal box. Make a hole on either side of the top. Cover one hole with foil and make a pinhole. Look into the other hole and see the conveniently projected image of the eclipse.

    • Don't use glasses, use the simplest camera obscura - a piece of black paper with a pinhole in it. Project the image on a sheet of white paper. Enjoy.

      If you want more, you know where to go, to the surplus shed :)

      If you want more, just do what Dr.Becky on YT recommended, hold up a colander and look at the shadow. If things get too intense you can use it as a hat to block the mind control rays.

    • by Toad-san ( 64810 )

      Yep, glasses be damned. Pinhole is fine for me.

      https://www.exploratorium.edu/... [exploratorium.edu]

    • It's actually cool to just look at the ground if there are trees around with smallish leave (birch, etc) - there will be lots of little crescents appearing.

    • Looking at the reflection of the Sun in a still bowl of water (though finding a black washing-up bowl could be challenging) works a well, and drops the light intensity to around 1% of the incident intensity without complex calibration. But it wobbles, so may not be suitable for your photographic plans.
  • This is just a conspiracy by big eclipse glasses to part you from your money. Just like with Iver***tin, don't listen to the people with a profit motive, just follow the safe squinting instructions and squint at the sun.

    Here's how:

    https://media.cnn.com/api/v1/i... [cnn.com]

  • People pay for special glasses?

    We use old AOL CDs. Perfectly safe.

  • Just watched the NOVA episode "Great American Eclipse" about the upcoming 2024 eclipse (links below) and it also warned against looking through a telescope or binoculars even while wearing eclipse glasses unless those devices also have a sun filter on them as they will concentrate the light too much for just eclipse glasses. (t=10m)

    - Great American Eclipse [youtube.com]
    - Great American Eclipse [youtube.com] (t=600s: telescope/binocular warning)

    - Great American Eclipse [pbs.org]

    • Yeah for sure - great way to cook telescope bits or cook your own glasses if you don't filter them. Same for cameras - unless you like turning sensors into goop.

    • You don't look through the binoculars, you use them to project an image of the sun on a flat white surface (6-8' away). That image is 6" - 18" across, is perfectly safe to watch, and you can use this technique to see sunspots (and planet Merc eclipses too!).
  • ...xkcd quote [xkcd.com].
  • There is both an ISO standard and a recognised list of glasses, based on the following video:

    https://youtu.be/jQR115jlyOc [youtu.be]

    Happy I saw this before buying, so I didn’t end up being too cheap and paying the price with my eyes.

      I did test mine out and you’d assume they weren’t letting anything through, until you look at the sun.

  • twenty five years ago you would take a 3.5 inch floppy disk, open it up and use the magnetic disk as a sun glass for that purpose. (suddenly makes me feel old...)
  • And all that you see
    All that you taste
    All you feel

  • Not something to buy off of Amazon - too likely to be fakes. I remember they had to do a bunch of recalls/warnings in 2017 over ones that were found to not meet standards.

    Too late now to by and get them anyway probably but go for trusted ones like American Paper Optics - and buy right from them. Same goes for camera or telescope filters.

    • I bought a Tiffen solar filter from B&H....

      They are a reputable company...

    • Tell us you didn't read (or understand) TFS without telling us you didn't read (or understand) TFS.

      The whole point was that these *were* from not only a trusted vendor, but one that had their product tested and put on a list of trusted vendors.

  • The amount of drama just because something is making a shadow is fucking nuts.
  • 95%+ of the people are going to pull out their phone and try to take pictures or videos of the thing anyway, so they can just look at their phone instead of the sun. Problem solved
  • Anecdotal Evidence: I was working in a medical device R&D lab in Oregon when there was an eclipse out there a few years ago. A coworker researched and bought the best glasses for the purpose and shared the info with his daughter. She bought the same pair on Amazon for less, but also ended up in the ER with burnt corneas. Turned out they were worthless bootlegs.

    I didn't bother with goggles. I'd experienced a full eclipse as a kid and I was more interested in experiencing the light. The way it changes
  • I got a pair of real eclipse glasses with my copy of Sky & Telescope's eclipse guide. They don't work very well with my glasses so I'll do the pinhole camera thing for the partial phases.

    Loved Dr. Becky's collander.

    ...laura

Dealing with the problem of pure staff accumulation, all our researches ... point to an average increase of 5.75% per year. -- C.N. Parkinson

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