With the total solar eclipse now just weeks away, the American Astronomical Society has advised people to take great care when viewing the celestial event. And that includes photographers.
Watching a solar eclipse can be a once-in-a-lifetime event but poses a significant risk to eyesight. Solar retinopathy is a condition caused by intense light exposure and can lead to serious and permanent damage to the retina; a sensitive layer of cells at the back of the eye. The retina processes human vision, converting light into neural signals that are received by the brain via the optic nerve.
“People want to go out and watch it, but there’s some bad information out there about how to watch the eclipse,” Dr. Ronald Benner, president of the American Optometric Association, tells Gizmodo.
Benner explains that the correct eclipse glasses must be worn to guarantee safety. These are glasses or eclipse viewers that adhere to the ISO 12312-2 Standard.
Benner says that any advice to wear dark sunglasses, or a welder’s mask, or double sunglasses should be disregarded because it is dangerous.
“Solar filters that provide safe, comfortable, unmagnified 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,” Rick Fienberg, project manager of the American Astronomical Society Solar Eclipse Task Force, says in a statement. “Such filters are at least 1,000 times darker than even the darkest sunglasses.”
Do I Really Need Proper Protection From the Eclipse?
But some may ask why they need to avert their gaze when the entire point of an eclipse is the Sun is blocked out by the Moon. The path of totality will span a width of approximately 65 miles but most of North America will see a partial eclipse. That means if the Sun pokes out from behind the Moon even for a second, the viewer is risking their eyesight by looking straight at the light,
“The retina is an extension of the brain—it’s a pure neural network back there. And when we typically look at light, we get a chemical reaction that turns into an electrical reaction that sends a signal to the brain,” Benner tells Gizmodo.
The incoming rays can burn out tissue and the damage can be permanent. Not only that, but the damage may not be apparent right away with the problem materializing in the weeks after. Benner likens solar retinopathy to a hole being punched in a photographic negative.
All of the above goes for looking at the eclipse through the viewfinder of a camera too. If you want to readjust the frame, look at the camera’s LCD screen. For more tips, read PetaPixel’s guide on photographing the eclipse.
Image credits: Header photo licensed via Depositphotos.