eclipse safe light levels

[SteveMe]

I am new to this forum and hope someone can help me.

I intend to go to the USA to see the total eclipse in 2017. I have read about safe ways of viewing the eclipse but it appears that for a short period of totality the eclipse can be viewed with the naked eye.

If this is true I would be concerned that the eye will become accustomed to the increasing light as the sun reappears and will not register an unsafe level of light.

Can anyone tell me
1. Is this true ?(viewing safely with naked eye)
2. At what light level and frequency is safe/unsafe for the naked eye?
3. Can a light meter be used to judge the level or does a dedicated UV or IR meter need to be used?

Steve

[Occulta]

Steve

During the partial stages of a Total Solar Eclipse you must never look directly at the Sun without proper eye protection; i.e by using Solar (Eclipse) Glasses or through a camera or telescope without a solar filter.

During totality it is perfectly safe to view the Moon (because you cannot see the eclipsed Sun) with your naked eyes.

As an eclipse chaser I usually work to a "5 second" rule - 5 seconds before totality before removing my glasses, and 5 seconds after before I put them back on. During this time I only glance at the view to catch the Diamond Ring or Baily Beads but for new observers I would strongly recommend you take your Solar Glasses off when you see the last bright spot (Diamond Ring) dissapear and put them on again as soon as you see the first bright spot at reappearance.

If you get the chance to view a Partial or Annular Eclispse you must always use eye protection as the Sun is in view during the entire event.

Light meters are a waist of time as you will miss the important parts of the spectacle.

There is a lot of misinformation regarding eclipse viewing but rest assured, viewing a Total Solar Eclipse during Totality - when the Moon fully covers the Sun - is perfectly safe with your naked eyes.

Chris

[Merlin66]

Chris says it all!
Good reading on the subject "Totality - eclipses of the sun" by Littmann, Willcox and Espenak.

[SteveMe]

Thanks Chris

Althought the 5 second rule seems a little unscientific I am willing to work with it as you seem experienced and to know what you are talking about. I would however like to know how you determine "5 seconds before totality". Is this on observed or calculated timing?

Steve