Eclipse viewers in the Louisville area are being cautioned to avoid looking at Monday’s celestial event with the naked eye.

University of Louisville professor of ophthalmology Dr. Patrick Scott says Louisville is not part of the eclipse’s “path of totality” and the sun won’t be completely blocked by the moon, even though it may appear to be.

Looking at it without proper solar filter glasses will expose the eyes to the sun’s harmful rays.

“It can go to the back of the eye and it can damage the retina, which is what we use to interpret light and give us our vision,” says Scott.

The University of Iowa and

Photo showing normal eye with normal optic nerve (solid white), macula (black), and vessels (dash).

American Academy of Ophthalmology

Photo showing solar photo-toxicity in the central retina, the yellow-white pigment irregularity highlighted by the arrow.

Looking directly into the sun causes a condition called solar retinopathy, which can leave a person with a mild to moderate reduction in vision, as well as central blind spots. There’s no treatment for the condition and Scott says the damage is permanent.

He says eclipse viewers should only use glasses that meet international safety standards.

“You should not be able to see anything else, other than the sun,” he says. “If you can see anything else, such as trees or whatever, it means the glasses are bogus.”

Scott says on the temple of the glasses, it should say “ISO 12312-2,” although some counterfeit glasses also have the code.

Another alternative for those without glasses is the pinhole projection technique.

Rick Howlett is host of WFPL's weekly talk show, "In Conversation."