19 Mar 2015

The solar eclipse: how you can view it

On Friday we will see the deepest eclipse of the Sun so far this century. For most of us, of course, the view will be ruined by cloud, fog and rain just as it was for the total eclipse in 1999.

But if you are lucky enough to have clear (or slightly cloudy) morning tomorrow, here’s some eclipse viewing do’s and don’ts:

DON’T: Be stupid. Life on earth has rubbed along with the sun quite well for the last 3.5 billion years. But looking straight at it for any length of time will damage your eyes. Sure, there is more temptation when most of it is covered by the moon. But even then, there’s still more than enough UV light making round to seriously damage your vision.

DO: Use cardboard “eclipse viewer” glasses. They must bear a “CE” stamp stating they’re suitable for looking at the sun. Using ordinary sunglasses or smoked glass, can be worse than looking with the naked eye (above) because you can get a higher dose of UV radiation in the eye. 

DON’T: Be really stupid. Looking at the eclipse through binoculars, a telescope or a camera lens concentrates the Sun’s rays. This will blind you. Instantly. The only exception is if specially designed solar filters are fitted.

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DO: Project the sun’s image though a pinhole in a piece of card. This is not a cop-out. You can’t look directly at the Sun so this is a really good way of watching the whole thing and enjoy it. For more info on projection techniques go here: http://www.ras.org.uk/images/solar_eclipse_leaflet.pdf

DON’T: Try and film or photograph the eclipse without a solar filter over your camera/smartphone lens. If you manage to avoid blinding yourself while framing up the shot the Sun is powerful enough to damage optics and sensors if filmed or photographed directly for more than a few seconds.

DO: Find out if there are any eclipse viewing events happening in your area. They are likely to have specialist equipment set up like telescopes and projections that will mean you get a far better look than in your own back yard.

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