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As looking at the sun is Not A Good Idea™. A common hack is to use a colander to project many instances of the eclipsing sun onto a surface.

The upcoming solar eclipse in Europe will be taking place during work hours and I would like to safely view it; working in an office, not a kitchen, I don't have access to a colander.

What office equipment can I use to safely observe the eclipse?

  • Any photographers in the office? Last time I watched an eclipse, I stacked three to four ND16 filters together and looked through that. Was it safe? I don't know, but I still have better than 20/20 vision. Use at your own risk. – TIO Begs Mar 24 '15 at 14:43
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    I don't think we're properly qualified to answer this question, and an incorrect answer could lead to permanent eye damage. Due to this, I think this question should be closed. – Wipqozn May 13 '15 at 11:24
  • @Wipqozn Locking this post until a consensus is reached on your meta question. – Mooseman May 13 '15 at 19:24
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    Can we just view it through cell phone cameras? I'm not sure if that could damage your camera lens, or if it would even show up. – goodguy5 Mar 31 '16 at 18:27
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A common method that I was taught at school is to create a pinhole projector type thing.

You can do this by making a small (pinhole) piercing in a sheet of paper and hold it above the ground until you get a small circle on the floor (which is the 'Sun') and you can safely watch the floor to see the eclipse progress.

You can also do it by interlocking your fingers at right-angles and the gaps between your fingers can act as the pinhole in this instance.

More information can be found here.

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Anything with a small hole, like these, to be used as a pinhole projector:

colanderhole punched papercdruler with holesselotapecotonreel

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    To make it clear. Things with small holes are intended to be used for projection of the solar eclipse. Looking at the sun through a small hole doesn't reduce the harm. – Alex Apr 17 '15 at 11:13
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    @Alex Added in your comment, and rolled back then changed your edit to have inline links. – Tim Apr 17 '15 at 11:19
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    Not really good examples for things with small holes! You need a really small hole (< 5mm) and you have to make sure that the projection surface lays in the shadow. So big holes and multiple holes and things with too less material around the holes are useless. – Byte Commander Apr 17 '15 at 16:39
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    Okay, as long as the light spots on the screen don't overlap, it might work. But big holes and things where the light might shine around it are not useful. Try it out. You could observe the wolfram wire of a light bulb with this method too. Then you see what works. The smaller the hole, the sharper (and smaller) is the projection you get. – Byte Commander Apr 17 '15 at 18:07
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    @ByteCommander Size of hole determines sharpness and brightness. Size of the image is determined by projection distance. Closer to the pinhole, the image is smaller, further away it's larger, but (in the case of the sun) the image will always be about 1/2 degree as measured from the hole. – Zeiss Ikon Mar 31 '16 at 18:49
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Remember the floppy discs? We dug one out from our storage, opened it up and looked through the film sheet.

Alternatively, a friend of mine took a lighter and a glass cup mat. He placed the glass mat above the lighter to get some soot onto it and watched it through the mat.

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    The soot method I've read is not good enough to fully protect. Not sure about floppies but you'd be hard pressed to find one in an office these days! – dav_i May 15 '15 at 6:47
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The silvered mylar wrapper on some kinds of candy or laser/copier toner, computer parts, etc. has such a thin aluminum coating on it that it's slightly translucent. Hold a piece that looks like a mirror up to the office lights; if you can easily see a fluorescent fixture through it, it's probably too thin, but if it completely (or almost completely) blocks the light from an office fluorescent, it's dense enough for safe viewing of the sun. As a bonus, your view will be much clearer than with a pinhole projection; I've used this method to view sunspots, which requires higher resolution than an eclipse.

Don't use this method with any kind of magnification; the extra light gathering of binoculars or a telescope might still let enough light in to damage your sight.

  • This is dangerous. What if you happened to use a film that blocks visible light but passes a lot of ultraviolet? You'd never know until your vision was harmed. – Daniel Griscom Jul 19 '16 at 12:13
  • All these reflectorized films use an aluminum coating, and aluminum reflects more UV than visible. If this kind of film is dark enough for the light tube test I gave, it will be UV/IR safe for reasonable duration. – Zeiss Ikon Jul 22 '16 at 11:32
  • All of them? That's a pretty broad statement when safety is involved. – Daniel Griscom Jul 22 '16 at 13:44
  • Do you know anything about the manufacturing of these films? You've downvoted and commented, let's leave it to the votes from here. – Zeiss Ikon Jul 22 '16 at 13:50
  • I hadn't downvoted, but now I have. – Daniel Griscom Jul 22 '16 at 17:56
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This is probably the most important part of this website. If you ever want to view a solar eclipse—whether it’s total, annular, or partial—the first thing you must know is this:

Never view the sun with the naked eye or by looking through optical devices such as binoculars or telescopes!

This is critical! Why? You may have taken a magnifying glass out into the sun and burned leaves with it. If so, you’ll remember that when sunlight is focused onto a small spot with a lens, it gets hot enough to start a fire. So understand this: you have a lens just like that in your eye. If you look at the sun, your eye’s lens will concentrate the sun's light and focus it onto a very small spot on the back of your eye, on the retina. This literally burns your eye, causing permanent eye damage or blindness. In additional, there are no pain sensors inside your eye—so you won't even know it's happening!

  • This doesn't really answer the question -- "what office supplies can I use to safely view an eclipse?" Safety is important, but so is accomplishing the intended task. – Zeiss Ikon Mar 31 '16 at 11:06
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    He probably wanted to comment, but due to the 1 rep he can't @ZeissIkon – Just Do It Mar 31 '16 at 17:48
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Solar Viewer for partial or total eclipses or sunspots

To make an effective and safe solar viewer for eclipses and sunspots, get a shoe box or larger and cut two 1" holes in one end and tape a white piece of paper to the inside wall opposite the holes.

Cover one of the holes with a piece of tin foil with a tiny round hole made with only the point of the smallest needle you can find and tape it with masking tape on all the edges.

The sharpest images are possible with a carefully-made, very small round hole with no burrs or tears.

Tape the box closed so there are no light leaks.

To use the Solar Viewer look through the peep-hole at a projection of the sun's image on the white piece of paper. Locate the peep-hole that you look through near enough to one edge of the box so you can put your eye very close to the hole. You want to block light to make the inside dark enough to see the dim image of the sun.

Aim the box so the light from the sun shows through the pinhole while you look through the other hole. You might have to use your hand to block some light to get a better view.

Try to make one and experiment long enough before the eclipse so you'll be ready when the time comes to enjoy it.enter image description here

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