• Lumidaub@feddit.org
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    19 hours ago

    Both eye glasses and magnifying glasses can be used to start a fire but both also take a bit to do so and have to be held in the exact right angle.

    • Em Adespoton@lemmy.ca
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      12 hours ago

      Right angle and focal distance. Eyeglasses sit such that the focal point concentrated enough to start a fire is a focal point further away than the back of your retina. But it can still cause permanent sunburn/vision loss.