Avoid Damage to Your Eyes During a Solar Eclipse

Preparing for the April 8, 2024 total solar eclipse.

There is a lot of buzz surrounding the time leading up to a solar eclipse. Viewing parties allow friends and family time to gather and experience a phenomenon that is rare in one lifetime. According to Space.com, “Every 18 months (on average) a total solar eclipse is visible from some place on the Earth’s surface. That's two totalities for every three years.” The rare factor, however, is that the Greater Sandusky Region lies right in the path of totality for this event. If you live in Sandusky, Norwalk, or surrounding areas, you are in for a real treat.

Given the fun and excitement connected with this celestial event, it’s important to be aware of the precautions to avoid permanent eye damage. Eric Dudenhoefer, M.D., an ophthalmologist at Parschauer Eye Center, responded to a series of questions we had related to the April 2024 total solar eclipse. Data from his responses were collected from the American Academy of Ophthalmology and the American Astronomical Society.

What can happen if I look at the sun?

Temporary or permanent injury to the retina can occur, leaving you with a blind spot in the middle of your vision.

How do I know if the sunlight has caused me vision damage?

If your eyes feel a little funny after an eclipse, it may not be a sign of solar retinopathy. Damage from the eclipse is unlikely to cause pain or discomfort in your eyes because the retina does not have any pain nerves. Instead, you would notice visual symptoms within four to six hours. But some may notice symptoms after 12 hours.

How long can I safely look at the solar eclipse without risking damage, even with proper eyewear?

If your eclipse glasses or viewers are compliant with the ISO 12312-2 safety standard adopted in 2015, you may look at the uneclipsed or partially eclipsed sun through them for as long as you wish.

What are the short and long-term adverse side effects of prolonged sun exposure?

If you are concerned that you may have sustained damage, here are some symptoms to look for:

• Blurry vision
• Headache
• A blind spot in your central vision in one or both eyes
• Increased sensitivity to light
• Distorted vision in which a straight line looks bent, or a door jamb looks curvy
• Changes in the way you see color, known as "dyschromatopsia"

What should I do if I think the sun has damaged my vision following the total solar eclipse?

There is no treatment for solar retinopathy. But it is important to see your ophthalmologist if you experience difficulties with your vision. An ophthalmologist will take a scan of the eye to see the extent of any damage. Many people recover after three to six months, but some will suffer from permanent vision loss, in the form of a small blind spot and distortion.

What should I do if I accidentally glance at the sun without proper eye protection during a solar eclipse?

While it is important to never look directly into the sun without proper protection, particularly during a solar eclipse, if you were to accidentally glance at the sun and then experience a change in your vision, medical attention via your eyecare provider should be sought.

Is there a certain point when I am able to look at the solar eclipse with the naked eye?

The only time that you can look at the sun without a solar viewer is during a total eclipse. When the moon completely covers the sun’s bright face and it suddenly gets dark, you can remove your solar filter to watch this unique experience. Then, as soon as the bright sun begins to reappear very slightly, immediately use your solar viewer again to watch the remaining partial phase of the eclipse.

Are there any safe methods for directly observing a solar eclipse without causing personal harm?

There is only one safe way to look directly at the sun, whether during an eclipse or not: through special-purpose solar filters. These solar filters are used in “eclipse glasses” or in hand-held solar viewers. They must meet a specific worldwide standard known as ISO 12312-2. These glasses will be available in a limited supply at Parschauer Eye Center for $5. Alternatively, you may wish to check with your personal eye care professional to see if they are making these glasses available.

You can also search on the internet for reputable vendors who have been screened by the American Astronomical Society here. Be careful of your source, as there have been problems in the past with counterfeit glasses being marketed as conforming to the standards when, in reality, they do not.

Keep in mind that ordinary sunglasses, even very dark ones, or homemade filters are not safe for looking at the sun.

How to safely watch a solar eclipse.

• Carefully look at your solar filter or eclipse glasses before using them. If you see any scratches or damage, do not use them.
• Always read and follow directions that come with the solar filter or eclipse glasses. Help children to be sure they use handheld solar viewers and eclipse glasses correctly.
• Before looking at the bright sun, stand still and cover your eyes with your eclipse glasses or solar viewer. After glancing at the sun, turn away and remove your filter—do not remove it while looking at the sun.
• Never look at the uneclipsed or partially eclipsed sun through an unfiltered camera, telescope, binoculars or other similar devices. This is important even if you are wearing eclipse glasses or holding a solar viewer at the same time. The intense solar rays coming through these devices will damage the solar filter and your eyes.
• Talk with an expert astronomer if you want to use a special solar filter with a camera, a telescope, binoculars or any other optical device.
• Another way to see the eclipse is through a pinhole projection or video display. A pinhole viewer lets you project an image of the sun onto another surface, like paper, a wall or pavement. The image of the sun is safe to look at throughout the eclipse. Learn how to make a pinhole projector or shop for one of these safe-viewing devices. Consider watching online or find an event at a local planetarium, science center or club where you know the right safety measures have been taken.

Is it safe to use homemade filters to view the solar eclipse?

No, it is never safe to use homemade filters to view the eclipse. Only use glasses or filters that conform to the ISO 12312-2 standard and which come from an eyecare professional or a site approved by the American Astronomical Society.

Conclusion

Firelands Regional Medical Center is directly within the path of totality for the April 8 eclipse. Residents and guests within the region will experience total darkness. Enjoy a safe and enjoyable day watching this spectacular event.