A man from Taunton, Peter Smith, has urged people to use proper eye protection when watching the solar eclipse on August 12, the BBC reports.
Twenty-seven years ago, Smith watched a solar eclipse using improvised protection—a borrowed welder's mask, which he believed would shield his eyes from the sun's rays.
However, the next morning he noticed flashes in his vision and experienced headaches. He later discovered that both of his retinas had been damaged. Smith is now urging everyone to use appropriate eye protection to watch the eclipse safely.
"Make sure you've got the right protection and filters to prevent any damage. Because once you get this kind of damage, it will never heal. It's not like cutting your hand," he said.
According to Smith, he still experiences the effects of looking directly at the eclipse.
"Even now, there is a residual impact. When I'm tired, sometimes a flashing dot comes back, and it's not pleasant when it does.
"If you're going to watch it, make sure everything you're using is appropriate," he warned.
Retinal damage can be irreversible
Taunton optometrist Sarah Farrant also warned that viewing the eclipse without proper protection can damage the retina and the macula—the central part of the retina responsible for the sharpest vision.
"The partial eclipse in the UK really means that people will want to look at the sun, but there is still enough light to cause damage even when the sun appears at its dimmest here in the UK.
"If you're not viewing the sun safely, you can end up with what we call a 'solar burn' at the back of the eye, and that can have a lifelong impact on the central part of your vision," Farrant explained.
How to safely watch a solar eclipse
The safest way to watch an eclipse is to use certified eclipse glasses that meet the ISO 12312-2 safety standard or to view the eclipse indirectly.
You should never look directly at the sun with the naked eye or through ordinary sunglasses, unfiltered cameras, binoculars or telescopes. Doing so can cause serious eye damage.
One simple way to observe an eclipse indirectly is to use a kitchen colander. Stand with your back to the sun and hold the colander above the ground. The holes will project multiple crescent-shaped images of the sun onto the ground.
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