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iceman
18-10-2012, 04:25 PM
I was contacted by the ASO - the Australian Society of Ophthalmologists, who are raising public awareness about the risks and dangers of an eclipse.

They've put together a handout and also have information on their website (http://www.aso.asn.au/index.php?option=com_content&view=article&id=38&Itemid=37).

Their advice is to turn your back to the eclipse, and not to use any direct viewing methods including using solar filters. They recommend to use indirect viewing methods such as pinhole projection (with your back to the eclipse), or to simply watch a webcast online.

They explain on their website (link above) the potential damage that can be caused.

And I also heard stories of people who suffered eye damage from the recent solar eclipse in China I think it was? No doubt because of unsafe viewing methods.

In part I'm presenting this information for the advice of the IceInSpace Community.


The other part of me says, with certified safe solar filters such as the IceInSpace Eclipse Glasses (http://shop.iceinspace.com.au/shop/iceinspace-eclipse-glasses/), it's perfectly safe to view the sun directly - but obviously care must be taken with children to ensure they are wearing them correctly.

For people who have experienced an eclipse, what are your thoughts?

I thought this thread could generate some interesting discussion.

bojan
18-10-2012, 04:33 PM
Nanny state...

Larryp
18-10-2012, 04:33 PM
ditto:screwy:

TrevorW
18-10-2012, 05:22 PM
I remember as a kid we used to view the sun through beer bottles

(bugger who put that chair there :cool:, it's always been there dear)

sheeny
18-10-2012, 05:42 PM
It does sound like it.

I suppose they recommend welders work behind their back too...:P

Al.

Kunama
18-10-2012, 06:26 PM
I can understand their concern which in many (most) cases is warranted for people will look at the eclipse unprotected during the period of totality (which in most case won't actually be totality due to their location). Many will stare through old negatives and other darkening media.

The more educated (hopefully everyone on this forum) will do it the right way with proper certified protection.

My brother-in-law is an Opthalmologist and my wife is the Opthalmology Research Co-ordinator for the Canberra Eye Hospital and the horror stories I have heard .....................

Check your solar filters, then recheck them and just to be sure check them once more ......... the eye damage through a telescope is totally painless and almost instantaneous !!!!

EDIT: an excerpt:
"Unlike glass filters, Baader film does not have a perfect cosmetic surface. Wrinkles, folds, kinks, pinholes and other imperfections in this film are normal and will be present on any Baader film solar filter purchased from us. These do not affect the image quality or safety of the filter. Pinholes, even at full solar intensity, work as a camera obscura. This means that each pinhole would project its own solar image, just like eyepiece projection. "

The above statement is from advertising material for a commonly used filtering medium ......... I personally would check for the abovementioned pinholes and try and use a piece of film not so afflicted ......... each his own I guess !

AndrewJ
18-10-2012, 06:29 PM
Any Triffids in FNQ????

Andrew

Allan_L
18-10-2012, 06:59 PM
There are obviously a lot of experts here who have experience in these areas, and assume everybody else does too.
How unfortunate if that proves not to be the case.

Whereas I agree that we are definitely becoming a nanny state, I do not see this thread as propagating that end.

So...
If you know what you are doing, do what you know,
but
if you are new to safe solar observing, better be safe than sorry, IMHO.

And even knowing it is perfectly safe during the total phase can be misleading, because the majority of Australians will not be in the "safe zone" during totality. And I dare say the warning is aimed at them.

Paul Haese
18-10-2012, 07:33 PM
Total crap. Yes take precautions but the total phase is perfectly safe to view directly. During the partials the eclipse glasses are just as safe. People not using correct protection are the ones that end up doing eye injury. They always do this as an arse covering exercise. Been to two totals now and not blind yet.

barx1963
18-10-2012, 07:58 PM
I think the thing to remember is that potentially a lot of people may attempt to look at the eclipse without a good understanding of what is going on. Yes, during totality it is perfectly safe, but for many people they may not comprehend that that safe period is only 2 minutes or so.
Many who will be interested are not astronomy minded or educated and the precautions need to be slated to them.
I think we as educated amatuers should be doing our utmost to ensure that everyone who wants to can view the eclipse safely.

Malcolm

strongmanmike
18-10-2012, 08:56 PM
It's probably better to listen to a careful Nanny than a drunk she-be-right Uncle....

:lol:

AndrewJ
18-10-2012, 09:20 PM
Or, alternatively, provide unbiased information based on facts, listen to both sides and make up your own mind.
Its about time people were told the risks and precautions
and then left alone.
Darwin will sort the rest out.

Andrew

strongmanmike
18-10-2012, 09:35 PM
Are you an uncle...? :question: :lol:

AndrewJ
18-10-2012, 09:59 PM
Gday Mike


Nope.
Just someone who believes i am responsible for myself.

Andrew

strongmanmike
18-10-2012, 10:14 PM
Good for you :thumbsup:

I ain't turning my back on the eclipse either

:cheers:

ourkind
19-10-2012, 01:11 AM
The only time I'll be turning my back on the eclipse is if there's an angry croc coming towards me :rundog:

GrahamL
19-10-2012, 05:24 AM
Thanks Mike, While most all of us are aware of the risks with solar
viewing many others arn't, passing on some timely and reasonable information from health profesionals is a good thing .

AstralTraveller
19-10-2012, 07:52 AM
:rofl::rofl:

Actually there is a good time to turn your back on the eclipse but it has nothing to do with eye protection. The Moon's shadow approaches from the west and you can see it coming! It will actually pass overhead just before totality producing strange lighting effects. So look west before second contact young man!

[1ponders]
19-10-2012, 07:54 AM
Now isn't this interesting Mike .

I don't know if you remember a couple of years ago I was in touch with Fair Trading/Consumer Affairs about the plastic solar filters that come with cheap scopes in an effort to get them banned. There was a thread about it somewhere, but according to FT; after contacting and speaking with "optical experts" and Ophthalmologists the little filters were fine to use :doh:

You now after years of using telescopes and solar filters I just feel so damn stupid. :rolleyes: Who do I believe:confused2: :confused2: :confused2:

:rolleyes:

pixelsaurus
19-10-2012, 08:07 AM
You can use a small plane mirror ( as found in cosmetic powder compacts) to reflect the sun's image onto a distant wall. I did it at the solar eclipse in Albany,WA in 1973. Dirt cheap and safer than direct viewing. I believe the theory is the mirror acts as an infinite series of reflective pinhole mirrors.

Shark Bait
19-10-2012, 08:36 AM
After calling for all to turn their backs the author of one of their papers has stated the following:

"Although we strongly advise against any direct viewing of the eclipse, if you decide to view the Sun directly use only "CE" marked standard solar filters and follow the manufacturer's instructions carefully."

Dr Rowan Porter (page 11, 2nd column, last paragraph)

http://www.aso.asn.au/images/stories/Dr_Rowan_Porter_-Turn_your_back_to_the_eclipse.pdf

The message that they are sending out is a little mixed.

I would have preferred to see a warning similar to what was printed in ASTRONOMY 2012 AUSTRALIA, page 5 (In the Shadow of the Moon). It gives accurate information regarding the risks involved and lets people know how to view the Sun in safety with solar filtered telescopes.

TrevorW
19-10-2012, 10:18 AM
Question

how many people do you know who have be blinded or had their eye affected by viewing an eclipse

me: none

how many people do you know who have cancer or some form or another

me: at least 3

Kunama
19-10-2012, 12:26 PM
I don't get the point of this post........
Unsafe solar viewing doesn't necessarily blind you instantly, the results of unsafe viewing are called 'solar retinopathy' where the intense/excessive light on the retina causes a release of various chemicals inside the eye which damage ones eyesight, the condition is painless and effects are not noted immediately, however, when you magnify the sun's intense light by placing your beautiful Apochromatic objective lens and eyepiece in the path between your eye and Sol you reduce the time required to do damage by approximately your FL/EP fl.

The advise given in the original post is aimed at the lowest common denominator, not the experienced astronomer, there really are people who will damage their eyesight watching this eclipse.
You would be surprised what people are capable of, like the 50 people blinded in India while staring directly at the sun hoping to glimpse an image of the Virgin Mary. It happens .............. and given that eyesight is rather an important part of this hobby of ours these things are worth considering.

Rob_K
19-10-2012, 01:03 PM
Thanks Mike, top marks to you for putting this advisory out there. :thumbsup: Whatever our own thoughts and experiences might be, the fact is that during an eclipse, some people will be blinded or have their eyesight seriously impaired. Small numbers and maybe they were doing something silly, but for the individuals affected this is a devastating change in their lives.

I don't have a lot of figures, but a World Health Organisation Fact Sheet in 1999 had this to say:

"Statistical evidence, accumulated mostly in developed countries, is scarce. Eclipse blindness is often underreported because patients consult eye specialists long after viewing an eclipse. In many cases, they do not associate their condition with looking directly at the sun for only a few seconds. In the majority of developing countries, such statistics do not exist at all.

That is why the official global figures of eclipse blindness and visual impairment do not look impressive. After the partial solar eclipse of 1952, for example, 52 cases of blindness or severe visual impairment were registered worldwide. After the 1970 and 1980 total solar eclipses, 145 and 112 cases of serious visual impairment were reported respectively."
https://apps.who.int/inf-fs/en/fact228.html

It happens (and will happen), so be careful! I won't be turning my back, but I will be taking every care. :)

Cheers -

Kunama
19-10-2012, 01:14 PM
Isn't it amazing that the results of viewing the sun in an unsafe manner can lead to the retina looking much like the sun that caused the damage, sunpots and all .......

cometcatcher
19-10-2012, 04:13 PM
They could have worded it a bit differently IMO. Saying solar filters are unsafe is like saying walking down the street is unsafe. It's a bit extreme.

They never went into filter details. I wonder if they had those now banned eyepiece filters in mind?

TrevorW
19-10-2012, 04:23 PM
[QUOTE=Kunama;906049]I don't get the point of this post........
Unsafe solar viewing doesn't necessarily blind you instantly, the results of unsafe viewing are called 'solar retinopathy' where the intense/excessive light on the retina causes a release of various chemicals inside the eye which damage ones eyesight, the condition is painless and effects are not noted immediately, however, when you magnify the sun's intense light by placing your beautiful Apochromatic objective lens and eyepiece in the path between your eye and Sol you reduce the time required to do damage by approximately your FL/EP fl.


My point is that statistically the numbers are small (nothing more)

I would hope that someone using a telescope would be prudent and smart enough to know the consequences and prepare against them.

Further more I take little interest in eclipses and if it wasn't for all the press etc I'd be oblivious to the fact that one was about to happen.

Some level of common sense must prevail and I would hope that in our educated society the dangers associated with looking directly at the sun in any circumstance, would be taught in schools from an early age.

Cheers:thumbsup:

xstream
20-10-2012, 04:56 PM
If the advice saves even one persons eye sight, it has been worth it! :)

bloodhound31
21-10-2012, 09:33 AM
Sounds like arse-covering to me. "You can view the eclipse through safe and approved filters etc, but we didn't tell you that."

AdrianF
21-10-2012, 07:35 PM
My opthamologist suggested not looking directly at welding even through a shield. Bit hard when that's what you do for a living.

Adrian

2stroke
21-10-2012, 09:00 PM
+1 That's all it is, They should really only be stressing about the use of solar filters and just advising that you should wear solar glass's. Though with the level of some peoples I.Q. and the fact they don't want to end up be sued i guess they have to go to these extreams in warnings. :question:

Jen
22-10-2012, 04:13 PM
When i was a little kid during the last total solar eclipse my mum wouldnt let me go outside to view it :mad2: i was so angry with her :shrug: so im making up for it this year yayyyyy

Danack
23-10-2012, 07:51 AM
So possibly a dumb question, how do you view the corona viewing during totality? Is it possible to view it directly though binoculars, or is it too dangerous to do that?

Also, I'm planning more take photos of the eclipse with a long lens. Is it worth slapping a UV filter on it to reduce the UV hitting either the camera sensor or my eye?

TrevorW
24-10-2012, 12:32 PM
Dan, I wouldn't run the risk of viewing it through binoculars unless they have suitable filters attached

Viewing the sun even during an eclipse without precaution could be dangerous to your health

Lee
25-10-2012, 04:35 PM
Agree 100% - was written by the ophthal college's lawyers no doubt....

PCH
25-10-2012, 04:47 PM
After reading Bojan's thread about the poor met office saps in Italy, - can you blame them ? :screwy: