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According to Kenneth R Lang in The Cambridge Encyclopaedia of The Sun visually observing the Corona during totality is hazardous.
Surprising advice from a reputable source.
I will be ignoring this on April 8th!
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Hi Steve,
How old is that book ?
He may have a point but during totality (after the Pearls disappear), it should be ok but having some ND1 or ND2 filtes may be helpful to cover your eyes could be helpful, depending on how bright the corona is. I have never been to a total eclipse, so I have no definite proof on that.
Kwong
Book is 2001 and by a very reputable author. Corona not bright, had to increase my cameras exposure in 2017 to capture it properly. Video best viewed with audio.
Indeed Steve, that is total BS written by someone who has clearly never seen a total eclipse so I think “reputable author” is rather kind. The surface brightness of the inner (K) corona is about 1 millionth of the surface brightness of the photosphere so similar to the surface brightness of the Full Moon. There is lots of very bad advice out there about looking at the totally eclipsed Sun. This is particularly awful:
https://jamanetwork.com/journals/jamaophthalmology/fullarticle/2816113
To quote: “It is not safe to view a total eclipse without added eye protection, even during the 90 seconds when an eclipse is total”. If people follow that advice on April 8 they won’t see much!
To be clear, during totality it is perfectly safe to view the eclipse with any optical aid you wish to use and no filters. I have always watched the 2nd contact diamond ring with the naked eye then switched to binoculars/telescope for totality and then gone back to naked eye as soon as the chromosphere appears just ahead of 3rd contact. For photography/video I’ve taken the filter off a minute or so before second contact and put the filter back after third contact. I have never had any sensor damage from doing that (although your experience may be different and I take no responsibility etc. etc.). My video from last April is here:
https://www.youtube.com/watch?v=QmoSTGQ6hpE
and it shows prominences and the inner corona for around a minute before and after totality.
Reading the JAMA link Nick gave, it looks like they think that you might be somehow taken by surprise by the Sun reappearing and instantly damaged.
Which is kind of weird as the end of totality is always easy to see coming and I must admit I have yet to hear of the Diamond Ring damaging anyone’s eyesight.
I could only imagine a problem for people whose eyes remained fully dilated (for some medical or pharmaceutically induced reasons) or who were using a telescope/binoculars during the Ring or forced themselves to keep staring after the Ring was over. Other than that, it sounds tosh to me. But, as Nick wisely says, your experience may differ*.
*Its a bit frustrating that everyone now needs to protect themselves from the wrath (legal or otherwise) of people not thinking about the potential consequences of their own actions.
Agree totally Nick. Well reputable as far as IAU is concerned!
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My 10×50 binoculars have travelled the world to several solar eclipses and I intend to use them again to observe during totality on April 8th. The eye and brain perceive the very fine details in the tenuous coronal streamers and the wide range of colour and contrasts in the chromosphere and prominences. Multi-image composite photography gives a representation of this stunning experience.
Which eclipse travellers plan to image comet 12P/Pons-Brooks during the 4 minutes of totality?
Alex.
I meant to add that I plan to spend a minute or so during totality using my 10x50s to look for the comet (the forum didn’t offer me an Edit option).
Alex.
Alongside imaging the Sun with a telephoto lens, I plan on using a DSLR with wide-field lens to capture Jupiter, Venus & 12P. It will all be automated so if it works it works and if it doesn’t I will still have a memory of the views of chromosphere and corona through a binocular!
I’ll be attempting to image 12P during totality. At 4th magnitude it should be fairly easy. At the 2020 eclipse I got C/2020 S3 (Erasmus) which was fainter (5th mag) and closer to the eclipsed Sun:
https://britastro.org/cometobs/2020s3/2020s3_20201214_1610_ndj.html
The trick will be to take lots of frames during totality, calibrate them with some very good flats and then stack them.
Seeing the comet visually will be very challenging. The sky will be fairly dark at this eclipse since the shadow is broad but it will probably be the equivalent of the western sky at the end of civil twilight. I’ve seen numbers such as 13 mag per square arcsec quoted. Think how hard it is to see a 4th mag comet in a very light polluted sky (say 16 mag per square arcsec). I’ll certainly be having a quick look with binoculars though!
Observers travelling to see the April 8th eclipse might be interested in this project
Alex.
Another bit of eclipse viewing stupidity. Apparently Amazon US are refunding people (using the dealers’ money) who bought SeestarS50 smart scopes because it might be dangerous to view the sun through it as the solar filter does not comply with the AAS filter advice !
https://www.cloudynights.com/topic/917434-seestar-warning-email/Hope you have clear skies today over there
today
tomorrow ! I am often told I dont know what day of the week it is, there is the evidence !
That is absolutely bonkers. So some people have ended up with free Seestars. I hope Amazon end up paying for this rather than the vendors.
It seems that total eclipses induce a kind of temporary madness in a large number of people. It must be something to do with those extra UV rays during he partial phase.
This was good advice on ABC News, especially item 4…
Alex.
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