A great, easy to read article in the Washington Post about the eclipse.
The basics: you can permanently damage your retina if you look without proper safety glasses. When the sun is normally full, it’s really hard to look at it for any length of time because it’s so bright that it hurts to look for more than a few seconds. Your eyes are protected because that brightness hurts. During a partial eclipse, the moon is blocking most of the light so it becomes easy to look without any noticeable pain but the light is still strong enough to burn your retinas; you just can’t realize it. Once the retina is burned, there is no healing or repairing that tissue. That can lead to permanent vision loss or even blindness. Its a tragedy that is easily avoidable by wearing eclipse glasses.
Further info can be found via the Today Show;
The bottom line is that you never want to look at the sun without protective lenses between your eyes and the sun. The ONLY time it is safe to look at the eclipse directly without protection is during the brief period of totality. This chart from NASA sums it up really well:
For eclipse glasses, you can find them all over- just make sure they’re actually marked with the ISO logo to show it’s passed ISO 12312-2 safety standard for safe eclipse viewing. Alternatively, you can view the transition through a welding lens- (of at least shade 12 though some feel that is too light and a shade 14 may be too dark) again, make sure it’s rated for eclipse viewing. NASA has a great list of how to watch on their site:
- Always inspect your solar filter before use; if scratched or damaged, discard it. Read and follow any instructions printed on or packaged with the filter.
- Always supervise children using solar filters.
- Stand still and cover your eyes with your eclipse glasses or solar viewer before looking up at the bright sun. After looking at the sun, turn away and remove your filter — do not remove it while looking at the sun.
- Do not look at the uneclipsed or partially eclipsed sun through an unfiltered camera, telescope, binoculars, or other optical device.
- Similarly, do not look at the sun through a camera, a telescope, binoculars, or any other optical device while using your eclipse glasses or hand-held solar viewer — the concentrated solar rays will damage the filter and enter your eye(s), causing serious injury.
- Seek expert advice from an astronomer before using a solar filter with a camera, a telescope, binoculars, or any other optical device. Note that solar filters must be attached to the front of any telescope, binoculars, camera lens, or other optics.
- Outside the path of totality, you must always use a safe solar filter to view the sun directly.
- If you normally wear eyeglasses, keep them on. Put your eclipse glasses on over them, or hold your handheld viewer in front of them.
If you are within the path of totality (https://go.nasa.gov/2pC0lhe (link is external)), remove your solar filter only when the moon completely covers the sun’s bright face and it suddenly gets quite dark. Experience totality, then, as soon as the bright sun begins to reappear, replace your solar viewer to look at the remaining partial phases.
Also, remember, if you are NOT in the path of totality, you cannot look at any part of the eclipse without protection! Even when it appears 99% total, you can still damage your retina without a safety shield.
I realize I am starting to sound like an old mother hen here about being safe and protecting your retinas from damage, but hey… at Tigard Eyecare, we like to keep everyone’s eyeballs safe.
One further thought about this whole event. I am a pretty passionate photographer who has way too much equipment that tempts me to try and photograph the event. But I am not even going to try, for 2 reasons:
Time spent relaxing and enjoying the moment sounds like a fantastic way to spend the morning. I’ll let all the astronomers and other pros take the photos. After all, this may be the largest, most photographed event in human history.