- It is not safe to look directly at the sun without proper eye protection, except during those fleeting minutes of a total solar eclipse, when the moon covers the sun completely. Viewing any part of the bright sun through a camera lens, binoculars, or a telescope without a special-purpose solar filter secured over the front of the optics will instantly cause severe eye injury, possibly even blindness.
- Astronomers say that counterfeit or fake eclipse glasses are flooding the market, prior to the April 8 total solar eclipse, which will be widely seen in North America. This information comes from the American Astronomical Society, the largest American society of professional astronomers, headquartered in Washington, D.C.
- This article gives you a way to test for fake eclipse glasses, and to be sure your eclipse glasses are safe.
Counterfeit or fake eclipse glasses polluting marketplace
With the April 8 total solar eclipse in North America just two weeks away, counterfeit and fake eclipse glasses are polluting the marketplace. As recently as March 11, the American Astronomical Society (AAS) Solar Eclipse Task Force hadn’t seen evidence that any solar viewers being sold for the eclipse were unsafe. But that has now changed. With millions of North Americans only now becoming aware that a solar eclipse is imminent and seeking to get their hands on eye protection, it is critical that everyone understand how to spot unsafe products.
Counterfeits vs. Fakes
Counterfeit solar viewers are ones that are made by one manufacturer but fraudulently printed with the name of a different manufacturer and perhaps with their artwork too. Until recently, the only counterfeit products we knew of were cardboard-frame eclipse glasses made by an unidentified factory in China but printed with “Mfg. by: American Paper Optics” (APO) on them. APO is one of the major U.S. manufacturers of safe solar viewers and prints its name and address on its eclipse glasses, whereas the Chinese copycat products have APO’s name but not its address. Thankfully, these particular counterfeits appear to be safe.
In recent days it has become clear that one or more unidentified factories in China are now producing counterfeit eclipse glasses printed with the name and address of a different Chinese factory, Cangnan County Qiwei Craft Co., which is known to manufacture safe products. Some also copy Qiwei’s artwork, and some include the name and/or logo of Qiwei’s principal North American distributor, Solar Eclipse International, Canada (SEIC).
Some of these newly identified counterfeits are indistinguishable from genuine Qiwei products and appear to be safe. Others look like Qiwei’s eclipse glasses, but when you put them on, you realize they are no darker than ordinary sunglasses. So, these products are not just counterfeit, but also fake. They’re sold as eclipse glasses, but they are not safe for solar viewing.
Safe solar viewers block all but a minuscule fraction of the sun’s ultraviolet (UV), visible, and infrared (IR) light. Overexposure to sunlight in these parts of the spectrum can cause severe eye injury, ranging from temporarily impaired vision to permanent blindness.
Rick Fienberg, Project Manager of the AAS Solar Eclipse Task Force and a veteran of 14 total solar eclipses, said:
Filters that provide safe, comfortable views of the sun generally transmit between 1 part in 100,000 (0.001%) and 1 part in 2,000,000 (0.00005%) of its visible light. Solar filters are at least 1,000 times darker than even the darkest regular sunglasses.
How to spot unsafe or fake eclipse glasses
If you didn’t buy your eclipse glasses directly from a vetted vendor, you may be wondering how you can be sure your glasses are safe. Feinberg said:
There’s no way to tell just by looking at them whether eclipse glasses are genuinely safe. But it’s easy to tell if they are not safe.
Before April 8, put them on indoors and look around. You shouldn’t be able to see anything through them, except perhaps very bright lights, which should appear very faint through the glasses. If you can see anything else, such as household furnishings or pictures on the wall, your glasses aren’t dark enough for solar viewing.
If your glasses pass the indoor test, take them outside on a sunny day, put them on, and look around again. You still shouldn’t see anything through them, except perhaps the sun’s reflection off a shiny surface or a puddle, which again should appear very faint.
If your glasses pass that test too, glance at the sun through them for less than a second. You should see a sharp-edged, round disk (the sun’s visible “face”) that’s comfortably bright. Depending on the type of filter in the glasses, the sun may appear white, bluish white, yellow, or orange.
If your glasses pass all three tests, they are probably safe. But if you aren’t completely confident of the safety of your eclipse glasses, you should use them sparingly. During the April 8 solar eclipse, look at the sun through the glasses for no more than 2 or 3 seconds every 5 minutes or so. This will be enough to observe the moon covering more and more of the sun before maximum eclipse, then uncovering more and more of it after maximum eclipse. Feinberg said:
Staring at a partial solar eclipse for more than a few seconds at a time, even through perfectly safe solar viewers, isn’t much fun anyway,. It’s almost impossible to detect the moon’s motion across the sun in real time except with magnification, and you must never look through magnifying optics while wearing eclipse glasses.
Solar filters for camera lenses, binoculars, and telescopes must always be securely mounted over the front of the optics.
How to tell if a solar viewer is truly safe
Solar viewers are safe if they comply with the UV, visible, and IR transmittance requirements of the ISO 12312-2 standard for filters for direct observation of the sun. You can’t just look for a statement to that effect on the product or its package. Anyone can print such a statement, but that doesn’t make it true. The only way to know for sure is to have the product tested at a laboratory that has been approved to conduct such tests by a recognized accrediting body.
The AAS Solar Eclipse Task Force has confirmed that all known U.S. and European manufacturers of solar viewers have had their products tested by properly accredited labs and shown to be safe. Some Chinese manufacturers have done so too, but others have had the tests done by labs whose accreditation is questionable or have left it to others to get the products tested.
The task force has compiled a list of vendors of safe solar viewers. For every seller on the list, we’ve confirmed three things: (1) the identity of the manufacturer, (2) that the manufacturer’s viewers have been tested for compliance with ISO 12312-2 by a properly accredited lab, and (3) that the viewers meet the standard’s transmittance requirements across the parts of the spectrum to which our eyes are at risk from overly bright light.
If you don’t see a vendor listed on the AAS solar eclipse website, it does not mean that their products are unsafe. We list more than 100 sellers of solar viewers, but there are hundreds more – especially on sites like Amazon, Etsy, and eBay – and we can’t possibly vet them all.
How and where to buy eclipse glasses
We used to recommend that you make sure the eclipse glasses you’re buying come from one of the manufacturers on our list. But now that we know that fake, unsafe eclipse glasses are being misrepresented as coming from at least one of these manufacturers, we need to urge a more cautious approach.
We now recommend that if you want to buy solar viewers online, buy only from sites you reach by clicking on the links from our list, or from a seller whose identity you can verify and whose name appears on our list. We recommend not buying eclipse glasses from random sellers in online marketplaces, even if they claim to get their products from a supplier on our list or to be approved by the AAS or NASA. (The U.S. space agency doesn’t approve or endorse commercial products, so any claim to the contrary is a warning sign that you’re not dealing with a trustworthy seller. Similarly, if a vendor claims to be on the AAS suppliers list but you can’t find it there, you shouldn’t trust them.)
If you already got your glasses from a source not on the AAS list, do the simple tests described above to make sure the viewers are not obviously dangerous.
Indirect solar viewing
If you have any concern that your eclipse glasses or other solar viewers might be unsafe, discard them or return them for a refund. If you can’t replace them with genuinely safe viewers, either because there’s not enough time or they’re sold out, you don’t have to skip the eclipse. As noted on the AAS Solar Eclipse Task Force’s eye safety page, there’s an alternative method for safe viewing of the partially eclipsed sun: indirectly via pinhole projection.
For an example of pinhole projection during the partial eclipse, cross the outstretched, slightly open fingers of one hand over the outstretched, slightly open fingers of the other, creating a waffle pattern. With your back to the sun, look at your hands’ shadow on the ground. The little spaces between your fingers will project a grid of small images on the ground, showing the crescent shape of the partially obscured sun.
Or just look at the shadow of a leafy tree during the partial eclipse; you’ll see the ground dappled with crescent-shaped suns projected by the tiny spaces between the leaves. A colander makes a terrific pinhole projector, as does a straw hat, a perforated spoon, a Ritz cracker, or anything else with small holes in it.
Keep in mind that you do pinhole projection with the sun at your back, and what you look at is the shadow of the projector, which will be superimposed with small images of the sun. Do not look at the sun through the pinholes! Note too that pinhole projection doesn’t work during totality, but that’s not a problem, because you can look directly at the totally eclipsed sun – which is no brighter than a full moon (and therefore not bright enough to project images through small holes) – without eye protection, as long as you stop looking or put your solar viewers back on as soon as the moon begins to uncover the sun and daylight suddenly returns.
Bottom line: With the total solar eclipse approaching, counterfeit and fake eclipse glasses are polluting the marketplace. This article gives you a way to test for fake eclipse glasses, and to be sure your eclipse glasses are safe.