How to Observe the Solar Eclipse
Things You Must Not Do
The Sun radiates very strong light and heat. At the time of the annular solar eclipse and partial solar eclipse, some parts of the Sun would be hidden with the Moon, however, it is not changed the strength of the light and heat. There is a risk that is to damage eyes, in the worst, lose eyesight if you observe the solar eclipse without correct methods.
Eyes would be damaged with using the following methods. So, you must not do that.
Watch the Sun directly with naked eyes. (it is dangerous even if a few seconds)
Use telescope or binocular (*1)
Use plastic sheets or CDs (*2)
Use film (*3)
Use the glass covered with soot 
Use sunglasses or goggles
Use telescope or binocular with wearing solar eclipse glasses
- *1 a telescope or binocular that is applied fading by professional could be used for solar eclipse observation.
- *2 a plastic sheets may be observing the sun has been released. [Oct. 17 2011]
- *3 the black-white photographic negative that is exposed and developed correctly by the professional could be used for solar eclipse observation.
Eyes would be damaged when you look at the Sun with the naked eyes even if the time is really short.
Also, please do not look at the Sun with the plastic sheet, CD, film, glass plate with soot, sunglasses, and goggles. These are not enough to cut the light, or easy through the light which has harmful wavelength even though you do not feel too bright to watch the Sun, thus the eyes would be damaged without realizing. However, it is safe to observe that plastic boards can be a safe solar observing.
Looking at the Sun with a telescope or binocular is more dangerous than that with naked eyes because these make the light and heat of the Sun stronger.
However, there is a risk to damage the eyes or lose eyesight in the worst when you observe the Sun without enough understanding and thorough knowledge of safe viewing methods. If you do not know about it well, please do not use own method, and please follow the professionals.
* These pictures were taken without looking the Sun not to give the damage to the eyes.
Safety Observation
Please read below guide carefully and observe the solar eclipse safety.