Unfiltered contact with upcoming eclipse can ruin your eyes — and your phone

There’s a total solar eclipse coming to New England on April 8, and there won’t be another one in the lower 48 states for 20 years. If you’re a photography buff, you may want to record the experience for posterity. So buy your safety glasses now, for you and your smartphone, if you plan to photograph this unusual event. Just as unfiltered light from the sun — eclipse or no eclipse — can cause permanent eye damage, it can also ruin your phone. Douglas Duncan, an astronomer at the University of Colorado, said it’s like what happens when you use a magnifying glass to concentrate a sunbeam and ignite a fire. A smartphone lens, he said, will do the same thing. “Eventually it would melt your camera,” said Duncan, “and it would be dead forever.” So cameras need the same sort of safety filter required for human eyes. Ordinary sunglasses aren’t nearly good enough. Real eclipse filters are made of glass or plastic combined with a coating that blocks almost all light. There are eclipse filters for every sort of camera, but these days, nearly all casual shooters rely on their phones. For them, Duncan designed a filter called Solar Snap, which sells on Amazon for about $17. It uses a Velcro attachment that sticks to the back of an Apple or Android phone and holds the filter in place over the lens. Solar Snap has been approved as safe and effective by the American Astronomical Society, and so have several other products that work much the same way. But Solar Snap also offers something extra — a smartphone app that allows the user to quickly adjust the camera settings and to shoot photos of the eclipse automatically. — HIAWATHA BRAY