FAQ about safely viewing solar eclipses

Viewing a solar eclipse can be exciting, but you must remember to protect your eyes before looking directly at our bright sun. Check out these frequently asked questions about viewing a solar eclipse.

Can I use my naked eyes to view the eclipse at totality?
Yes, BUT only during the brief moment of darkness when the sun’s disk is completely covered and the sky goes dark (1 minute to 2 minutes, 41 seconds, depending upon your location). During this brief moment of darkness is the only time the sun can be directly viewed—only for a moment, however, as the corona of the sun can still be seen and is extremely bright. This is never true for annular or partial solar eclipses! NEVER look at the sun, except during totality, without approved solar-viewing devices.

How do I know if my glasses or solar filter is “approved”?
Approved solar filters have met the ISO 12312-2 international standard for such products. Experts suggests that one widely available filter for safe solar viewing is number 14 welder's glass. It is imperative that the welding hood houses a #14 or darker filter. Do not view through any welding glass if you do not know or cannot discern its shade number. Be advised that arc welders typically use glass with a shade much less than the necessary #14. A welding glass that permits you to see the landscape is not safe. Inexpensive eclipse glasses have special safety filters that appear similar to sunglasses, but these do permit safe viewing.

Can I wear welder’s goggles to protect my eyes when I look through my small telescope, binoculars, or camera’s viewfinder?
It is NEVER safe to look through a camera, binoculars, or a telescope at the sun without approved solar filters securely attached, as these devices are designed to magnify and focus the intensity of the sun at the eyepieces. Therefore it is important that the sun's light is safely filtered where the light first enters the device.

Can I use my polarized sunglasses to look at the sun? What if it is brief?
It is NEVER safe to look directly at the sun with any type of sunglasses! The solar filters found in "eclipse glasses" are the only glasses appropriate for looking directly at the sun.

Can I use a piece of Mylar to look directly at the sun?
Yes, Mylar filters made to look at the sun are commercially available. However, Mylar from a broken Mylar balloon is not adequate, as it may have a semi-porous coating. Mylar filters specifically made for looking at the sun are made to a higher quality standard and are darker than Mylar in products not designed for solar observing.

Can I use my straw hat to look at the sun?
No, not directly. A method known as "pinhole projection" can be done through any pin-sized hole. It is important to focus and project the sun's image onto the ground or another surface to see the sun's disk. It will appear white with a "bite" out of it during the eclipse. You may even see a sunspot or two on the sun's disk. But you CANNOT look through your hat directly at the sun!

Galileoscope Solar Filter
Only view an eclipse through special-purpose “eclipse glasses” or hand-held solar viewers that meet the ISO 12312-2 international standard for such products.

Photo by Mark Margolis / Rainbow Symphony

Last updated: March 14, 2017