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Solar Viewing Safety:

A solar eclipse of any kind can be a once in a lifetime thrill that everyone should be able to enjoy, but there is a right way to do it.

This page serves as a guide on how to view the Sun safely. THE SUN SHOULD NEVER BE VIEWED WITH THE EYE OR TELESCOPE WITHOUT THE AID OF SPECIAL FILTERS - using a mirror to view a direct reflection is the same as looking directly at the Sun. If you believe you have decreased vision as a result of viewing the Sun directly, see an eye care specialist (Ophthalmologist) immediately. Unfortunately, damage to the retina from direct Sun exposure is permanent and there is no treatment. This condition is called Solar Retinopathy. I work in the eye care field as an ophthalmic photographer and have seen this condition all to often.

Note: Solar Retinopathy is a condition that affects the central visual acuity only - meaning the part of the eye (retina) that we use to read. While total blindness will not occur, central blindness can occur.

However there is one, and only one, case in which the Sun can be safely viewed directly with the eye and that is during a Total Solar Eclipse. During a Total Solar Eclipse the Moon covers the entire face of the Sun preventing any direct sunlight from reaching the observer.

Using a telescope with a special solar filter will allow direct viewing of the Sun, and there are special telescopes and tools that can be used to view the Sun and image of the Sun safely. But first, here are the three types of Solar Eclipse with a short narrative by me on safely viewing them. See the Solar Viewing Equipment section below for more information on how to safely view the Sun.

For more information, please read NASA's Eye Safety During Solar Eclipses.

NOTE: This is not to be confused with a Lunar Eclipse, which CAN be viewed with the eye.

This is a partial solar eclipse. During a partial eclipse, the Moon only covers a portion of the Sun - any position of the Moon as long as the Moon is not directly in front of the Sun. How much of the Sun is covered depends on the path of the Moon. During a partial eclipse, there may be a noticeable decrease in overall brightness but do not let that fool you as there is still plenty of damaging sunlight that can burn the retina if viewed directly.

Safety requirements: use either solar eclipse glasses, solar filters on a telescope or a solar viewer device. NEVER look at a partial eclipse with an unaided eye. Sunglasses will not help!

An annular solar eclipse is seen here. In this case, the Moon is directly in front of the Sun, but because of the elliptical orbit of the Moon about the Earth, it can be further away from us thereby looking smaller - hence not covering the entire solar surface. It is probably OK to look at the Sun directly once the Moon has covered the face of the Sun, but I personally would advice against this.

Safety requirements: use solar eclipse glasses, solar filters on a telescope or a solar viewer device. It might be safe to view the eclipse once the moon has covered the sun, but prudence reigns supreme. Total eclipse time can vary from a few seconds to a minute or more so have your solar tools ready when the Moon passes over the Sun.

A total solar eclipse is seen here. A total eclipse occurs when the angular diameter of the Moon equals the angular diameter of the Sun (based on orbital motions of the Moon) and the Moon is able to cover the entire face of the Sun. During this time, the Sun can safely be viewed with the eye. But have your solar viewing gear ready as the Moon takes a few seconds to a few minutes to traverse the Sun's face.

Safety requirements: use solar eclipse glasses, solar filters on a telescope or a solar viewer device TO TRACK THE ECLIPSE until the Moon covers the Sun's face. Total eclipse time can vary from a few seconds to a minute or more so have your solar tools ready when the Moon passes over the Sun.

I wish to repeat a statement made in the Safety Requirements above, and that is using Sun observing tools to track the path of the Moon near the Sun. Until the Moon fully covers the Sun, these tools should be used for safety.

A Solar Eclipse is a wonderful phenomenon to behold. Viewing one safely by using the right tools will ensure that you can enjoy the next Solar Eclipse!

And remember, unlike a Solar Eclipse a Lunar Eclipse does not require any observing aids.

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Solar Viewing Equipment:

Solar safety is very important. Permanent blindness can occur of one looks directly at the Sun. Luckily there are several tools available for safely viewing the Sun:

  1. Solar Eclipse Glasses
  2. Solar Filters for binoculars and telescopes
  3. Specialized Solar telescopes
  4. Indirect viewing of the Sun using a projection viewer

The Coronado website has an excellent page on filter safety when viewing the Sun with filters. I won't repeat it here but you can be directed to the page here.

Solar Eclipse Glasses are a type of sunglass that use neutral density filters to block out a large portion of brightness from the Sun. An example is a product sold by Rainbow Symphony called Eclipse Shades.
A variety of companies offer a full aperture white light solar filters that fits over the objective lens of a telescope. Offered in a variety of sizes, these filters block out 99.999% of all sunlight which allows for safe viewing.

Using these types of filters, viewing of the Sun's surface with the eye and a camera is possible. Sunspots (if present) will be visible.

The image on the left is an example from Orion Telescopes, but other companies are: Lumicon, Thousand Oaks Optical, Baader Planetarium and Coronado.

Orion Telescopes offer a really interesting idea of white light solar filters for binoculars. Just like the white light filters above, they also block 99.999% of sunlight allowing for safe viewing of the Sun.
Coronado is a company that makes, what I believe is the only specialized Solar Telescope. These utilize special filters called Hydrogen-Alpha filters that allow spectacular views of the Sun's upper atmosphere. But beware, they are expensive - but worth every penny!

With this type of telescope, direct solar viewing is possible.

Indirect viewing of the Sun is probably the safest method available. One uses a project to project the Sun's image on a surface, and the observer is simply viewing the reflection.

A perfect example of this is a product called Solarscope. This uses the same principle as the shoebox camera (take an empty shoebox, poke a hole on one end and use a piece of paper on the other end to view the Sun's image) but does it in a way that several people can view at one time.


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