Punch a pinhole in an index card and hold it 2 to 3 feet (0.6 to 0.9 meters) in front of another index card. The eclipse can be viewed safely through the hole. Encase the index card contraption in a box, using aluminum foil with a pinhole, and you’ll see a sharper image of the eclipse. You may also purchase special glasses with aluminized Mylar lenses. Damage to the retina can occur if the eclipse is viewed with other devices such as photographic filters, exposed film, smoked glass, camera lenses, telescopes, or binoculars.