Eclipse tips: Don't go blind

W ith all the scuttlebut on eclipse watching, the Post has gleaned from a variety

of sources, including a report produced by the NASA Center for AeroSpace Information,

the following recommendations for those who want to observe this rare event:

• The sun can be viewed safely with the naked eye only during the few brief seconds

  or minutes of a TOTAL solar eclipse.

• Partial or annular solar eclipses are NEVER safe to watch without taking special

  precautions.

• Do not attempt to observe the partial or annular phases of any eclipse with the

  naked eye.

• Failure to use appropriate filtration may result in permanent eye damage or BLINDNESS!
• Unsafe filters include color film, some non-silver black and white film, smoked

  glass, photogrphic neutral density filters and polarizing filters.

Solar filters designed to thread into eyepieces and often sold with inexpensive telescopes

are also dangerous.

• Do not experiment with other filters unless you are certain that they are safe.
• Damage to the eyes comes predominantly from invisible infrared wavelengths.
• The fact that the sun appears dark in a filter or that you feel no discomfort

  does not guarantee that your eyes are safe.

• The safest way to view the eclipse is by using projection, in which a pinhole

  or small opening on a piece of cardboard is used to cast the image of the sun on

  a screen or sheet of white paper placed a half-meter or more beyond the opening.

Projected images of the sun may even be seen on the ground in the small openings

created by interlacing fingers.

• Binoculars can also be used to project a magnified image of the sun on a white

  card, but one must avoid the temptation of using these instruments for direct viewing.

The eclipse passes over Angkor Wat for one minute and 48 seconds at 10:58am on

Oct 24.