Safe Solar Eclipse Viewing: Water Reflection

While it may be tempting to look directly at a solar eclipse, it is unsafe to do so unless the moon is completely blocking the sun. Even a sliver of sunlight can be potentially blinding. So, what are some safe ways to view an eclipse? One popular method is to use a pinhole projector, which can be made by crossing your outstretched, slightly open fingers over the outstretched, slightly open fingers of your other hand, creating a waffle pattern. With your back to the sun, look at the shadow cast on the ground by your hands. The little spaces between your fingers will project a grid of small crescent-shaped images on the ground. Another method is to use a kitchen colander. With your back to the sun, hold up the colander and place a piece of white paper or card behind it. The colander will project multiple images of the eclipse onto the paper. A third method is to watch the reflection of the eclipse in a bucket of water. However, optometrists advise against looking at the reflection for extended periods, as even reflected sunbeams are too strong for the eyes.

Optometrists advise against it

Optometrists advise against viewing an eclipse through a reflection in water. Even when the sun is partially eclipsed, it remains unsafe to view without protective glasses. The sun's strength is unchanged during an eclipse, and even a sliver of sunlight can be potentially blinding. Staring at the sun's reflection in water can damage your eyes in as little as 100 seconds.

The only safe way to view an eclipse is by using special-purpose solar filters, such as "eclipse glasses" or handheld solar viewers. These filters comply with the ISO 12312-2 international standard for eye safety. It is also safe to view an eclipse indirectly via pinhole projection. For example, you can create a waffle pattern by crossing the outstretched, slightly open fingers of one hand over the other. With your back to the sun, look at the shadow cast on the ground. The small spaces between your fingers will project a grid of images showing the sun as a crescent.

Ordinary sunglasses, even very dark ones, are unsafe for looking at the sun. The same is true of welding goggles, which must comply with the ISO standard to be safe for eclipse viewing. It is also unsafe to look at the sun through a camera, telescope, binoculars, or other optical devices, even when wearing eclipse glasses.

It is important to remember that during a partial or total solar eclipse, it is unsafe to look directly at the sun unless it is in the brief total phase ("totality") when the moon entirely blocks the sun. At all other times, special-purpose solar filters are necessary to protect your eyes.

Even reflected sun rays can damage eyes

The retina's photoreceptors, even when overloaded, can function for hours before they are disabled. The retina does not have any pain receptors, so there is no immediate discomfort or pain associated with the damage. People may not realise what has happened until hours later or even the next day. Once the photoreceptors are shut down, people may experience blurred or distorted vision, trouble focusing on faces or printed pages, or a spot in the centre of their vision known as a scotoma.

While it may be tempting to view a solar eclipse via its reflection in water, it is not a safe method. If even 1% of the sun is showing, it is enough to seriously damage your eyes.

The only time the sun can be viewed safely with the naked eye is during a total eclipse when the moon completely covers the sun. It is never safe to look at a partial eclipse without the proper equipment and techniques.

To view a solar eclipse safely, use special-purpose solar filters such as eclipse glasses. These glasses block approximately 99.99% of light rays.

You can use a bucket of water to view an eclipse

If you are going to use the bucket method, make sure the bucket is filled to the brim with clean water. This will give you a clear reflection, allowing you to take excellent photographs of the eclipse. You can also use any body of water, such as a garden pond or lake, to view the eclipse. However, it is important to remember that you should not look directly at the eclipse, as it will damage your eyes.

There are safer alternatives to the bucket method. One way is to use a pinhole projector. For example, you can cross your outstretched, slightly open fingers with the outstretched, slightly open fingers of your other hand, creating a waffle pattern. With your back to the sun, look at the shadow cast by your hands on the ground. The little spaces between your fingers will project a grid of small images of the sun on the ground, showing a crescent during the partial phases of the eclipse. You can also use a colander, which makes for impressive viewing of the eclipse. Stand with your back to the sun and hold up the colander with white paper or card behind it. This will project multiple images of the eclipse onto the paper.

Another safe way to view an eclipse is to use special-purpose solar filters, such as "eclipse glasses" or handheld solar viewers. These must comply with the ISO 12312-2 international standard. Do not use ordinary sunglasses, as they transmit far more sunlight than is safe for your eyes.

You can also use a colander to view an eclipse

While it is unsafe to look directly at an eclipse, there are several safe methods to view this spectacular event. One such method is to use a pan of water. However, it is important to note that this method may not provide a clear view, and there are other safer, more effective alternatives.

To use a colander for eclipse viewing, simply hold it out over the ground so that sunlight shines through the holes. The shadow of the colander will look normal, but each hole will project a crescent-shaped image of the sun, allowing you to safely watch the eclipse unfold.

This method is not only effective, but it's also a lot of fun and will make you look like a creative eclipse viewer rather than someone simply staring at the sky. It's a great way to get the whole family involved in the experience, and you can even try it out with different types of colanders or strainers to see the various effects they produce.

So, if you don't have eclipse glasses or want to try something different, grab a colander from your kitchen and head outside to enjoy the eclipse safely and in style!

It's still dangerous to view an eclipse through your phone

It is still dangerous to view an eclipse through your phone, even with protective eye gear. While it is well known that staring at the sun can permanently damage your eyes, the sun can also damage other image sensors, like those in cellphone cameras.

NASA warns that smartphone cameras were never designed for taking photos of the sun or the moon. Standard lenses are very small and aren't equipped with the resolution needed for the largest objects in the sky, like the sun and moon.

"Cellphone cameras do not have the kind of protective filters needed for safe or successful solar photography," says Dr. Geoff Bradford, professor of ophthalmology at West Virginia University.

Photographing a partial eclipse with a smartphone will likely damage the camera sensor and result in an overexposed photo. Even during totality, when the sun is completely obstructed, experts warn against looking up at the sun because of how suddenly sunlight can reappear.

"Totality of the eclipse lasts only about 1 to 3 minutes based on geographic location, and bright sunlight suddenly can appear as the moon continues to move," an eclipse viewing guide published in JAMA noted, adding that "even a few seconds of viewing the sun during an eclipse" can temporarily or permanently damage your vision.

If you want to view an eclipse, the safest way to do so is with eclipse glasses that meet the international standard, ISO 12312-2, according to the American Optometric Association.

If you want to take pictures of an eclipse, experts recommend using a proper filter over your phone's camera lens, such as eclipse glasses or another type of protective filter.

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