You’ve heard the warnings by now: Don’t stare directly at the sun today during the solar eclipse — it could damage your eyes.
Here’s a look at what happens if you do decide to ignore all the warnings and cautionary tales.
YOUR EYES AND THE ECLIPSE
Like a camera lens, your pupils dilate, or open, in darkness to allow in more light. In Boston on Aug. 21, the overall sunlight will be dimmed, like when clouds cover the sun. But if you look at the partial eclipse, the portion of the sun that is visible can cause permanent damage to your eyes.
Prolonged exposure to the sun’s light can cause “retinal burns.” Exposure can damage or even destroy cells in the retina (back of the eye) that transmit what you see to the brain. The damage can be temporary or permanent and occurs with no pain. It can take a few hours to a few days after viewing the solar eclipse to realize the damage that has occurred.
■ Distorted vision
■ Altered color vision
■ Loss of central vision
SAFE WAYS TO VIEW
Some safe ways to view the solar eclipse from any New England vantage point:
■ Welder’s glass: Number 14 welders glass. It can be found at local hardware and home-improvement suppliers.
■ Mylar filters: Aluminized mylar plastic sheets are available as eclipse vision glasses or can be cut and made into a viewing box.
■ Pinhole projection: Make a pinhole in a sheet of cardboard and hold it between the sun and a sheet of white paper on the ground.
HAVE OTHER PEOPLE SUFFERED AFTER AN ECLIPSE?
Two men are warning people about the dangers of staring at the sun during the eclipse after they did so decades ago in Portland, Ore.
More than 50 years ago, Louis Tomososki and Roger Duvall stood and waited, squinting toward the sky. Sure enough, the teenagers eventually spotted what they had been looking for: a partial eclipse of the sun.
Both men, now 70, say they wish they had known about the long-term harm that afternoon would do to their eyesight.
‘‘We didn’t know right that second that we damaged our eyes,’’ Duvall said in a phone interview Sunday. ‘‘At that time, we thought we were invincible, as most teenagers do.’’
Both estimate they had glanced up for about 20 seconds or so — each using a different eye. Immediately afterward, Tomososki’s right eye and Duvall’s left eye bothered them slightly.
‘‘We had looked down at the ground and you’re still looking at part of the eclipse like it’s imprinted in your eye,’’ Duvall said.
It was only through separate eye exams later that both men learned they had permanently damaged their retinas. For Tomososki, his ‘‘good eye’’ compensates for his ‘‘bad’’ one when both are open. When his left eye is closed, however, he sees a ‘‘scrambled, whitish spot’’ through his right eye.
‘‘Have you ever seen a news story where they don’t want the license plate seen at home? That’s the exact same color of everything, except mine’s the size of a pea,’’ he said. ‘‘And that was 20 seconds worth of burning. If we had looked longer — or the worst thing, if you switch eyes looking at the sun — then you’re in real trouble.’’Material from The Washington Post was used in this report.