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Watsisname
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Total Solar Eclipse 2017

05 Sep 2017 01:43

A-L-E-X wrote:
Source of the post Now that is kind of scary, do you think people who have seen a lot of eclipses say that because they might've damaged their eyesight somehow?

I highly doubt it, and most first time viewers also describe it that way.  (I was amused to hear Pecos Hank describe it as "the blackest black you'll ever see" in his video, since I've seen many others use very similar language.)  To me this suggests that the totality blackness illusion is so strong that most people feel the need to use strong words to describe it.

With regard to eye safety, it is surprisingly difficult to look at the Sun outside of totality.  Within seconds it is too bright to look at -- Midtskogen's comment that it quickly becomes like a welder's torch is quite accurate.  You can glance at it, which is safe just as when the Sun isn't eclipsed, and your instincts tell you to look away before any damage can occur.  I was actually surprised by how strong my instinct to look away from the diamond ring was.  It takes deliberate effort to stare to the point of damaging your vision, and I think most veteran eclipse chasers would know better than to do that.  Staring at it doesn't reveal anything anyway.  You can't see the crescent shape.

But during totality, there's nothing dangerous about looking at it at all.  Many have been told that there are still dangerous rays or something that would damage your vision.  I even overheard someone say that in Madras.  These claims are fantasy and ignorance, and is still sadly common in some countries with officials warning their citizens not to look.
 
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Total Solar Eclipse 2017

05 Sep 2017 02:31

Yes, many people believe that watching the totality is dangerous, perhaps because they hear so much about protection during partial eclipses.  I had to convince at least one guy during my visit that totality is totally safe to watch with the naked eye.

I think that trusting your reflexes is good enough and no special awareness is necessary, with the major exception that every move involving a telescope or binoculars must be thought through first.
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Total Solar Eclipse 2017

05 Sep 2017 02:43

Yes and I don't buy much into the fear-mongering about eclipses and honestly don't own or wear a pair of eclipse glasses- they look rather ridiculous.  I've looked at an annular eclipse with 10x50 binoculars and not had anything happen- my vision is pretty bad anyway- 20/80 in one eye and 20/35 in the other (I actually see much better when I close one eye lol.)  And honestly a little vision damage is worth it to see such an amazing sight.
Last edited by A-L-E-X on 05 Sep 2017 02:47, edited 1 time in total.
 
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Total Solar Eclipse 2017

05 Sep 2017 02:46

Watsisname wrote:
A-L-E-X wrote:
Source of the post Now that is kind of scary, do you think people who have seen a lot of eclipses say that because they might've damaged their eyesight somehow?

I highly doubt it, and most first time viewers also describe it that way.  (I was amused to hear Pecos Hank describe it as "the blackest black you'll ever see" in his video, since I've seen many others use very similar language.)  To me this suggests that the totality blackness illusion is so strong that most people feel the need to use strong words to describe it.

With regard to eye safety, it is surprisingly difficult to look at the Sun outside of totality.  Within seconds it is too bright to look at -- Midtskogen's comment that it quickly becomes like a welder's torch is quite accurate.  You can glance at it, which is safe just as when the Sun isn't eclipsed, and your instincts tell you to look away before any damage can occur.  I was actually surprised by how strong my instinct to look away from the diamond ring was.  It takes deliberate effort to stare to the point of damaging your vision, and I think most veteran eclipse chasers would know better than to do that.  Staring at it doesn't reveal anything anyway.  You can't see the crescent shape.

But during totality, there's nothing dangerous about looking at it at all.  Many have been told that there are still dangerous rays or something that would damage your vision.  I even overheard someone say that in Madras.  These claims are fantasy and ignorance, and is still sadly common in some countries with officials warning their citizens not to look.

I looked at a 70% partial eclipse just with sunglasses and a 90% annular eclipse with 10x50 binoculars (it was mostly cloudy that day and the binoculars helped make it more clear.)  Looking directly at the sun there's too much glare to see anything so the sunglasses helped a great deal.  One thing I noticed through the partial phase was that the moon seemed much smaller than the sun, I think it was because the sun seemed artificially larger because its glare made it seem larger than it actually was.  The closest analogy I can think of is a cookie and the moon taking small bites out of the cookie.
 
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Total Solar Eclipse 2017

05 Sep 2017 02:48

I was actually more nervous about damaging my telescope or my camera- ironically enough.  I've read that the sunlight can damage the camera's sensor (its bayer color filter array) as well as telescopes.

By the way I was getting berated on Twitter for telling people the same things you guys just said lol.  One guy said he volunteered at a hospital and saw "hundreds" of people coming in with vision damage from looking at the eclipse and when I told him my eyesight was fine he said "the retina can't feel pain and you won't know for 24 hrs what you just did to your eyes" and I then told him that I saw an annular eclipse in May 1994 through 10x50 binoculars and nothing happened and then he shut up lol.

What you said about some countries actually also happens right here in the US. I heard stories about schools keeping their children in classrooms even after the school day was done all because they didn't want them looking at the eclipse- what do you think of that?!  Some people even told me about their childhood experiences of their parents keeping them in the basement because they didn't want them going outside during the eclipse and they've been afraid of them ever since- this is like the modern version of what people in ancient times thought, see we aren't as advanced as we thought we were.  It's a real pity because they missed out on something grand and a lot of children have a natural interest and genuine curiosity about astronomy and stuff like this ends it.  I wanted to scream at them "WHAT AND YOU THINK LETTING YOUR KIDS PLAY VIDEO GAMES AND WATCH TV FOR 4 OR MORE HOURS A DAY IS GOOD FOR THEIR EYES (or for their brains for that matter)?"

About the telescope and camera cautiousness, why is that? I was worried I might damage my equipment more than I was worried about my eyes lol.
 
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Total Solar Eclipse 2017

05 Sep 2017 03:26

Without eye protection there's not much to be seen during a partial eclipse.  So if people hear that there is an eclipse and they don't have filters or glasses and really want to see it, it's understandable that they're told not even to try have a look.  The school's fault in your example is not keeping the children in, but failing to provide the means to observe it.

EDIT: As for damaging telescopes and cameras, you need to think of where the focal point is - in particular if it's on your retina or camera sensor.  A narrow view (and sometimes even a wide view) projected on the sensor will permanently damage it.  It's important to have in mind for video cameras or DSLR's with live view when the sensor is exposed for an extended time.

I forgot to point away my 1000 mm after totality in Madras, so for perhaps one minute it was directly pointed to the sun, but there was little to worry about really, since the mirror was directing the focus out of the viewfinder and into thin air, and 1% sunlight wont heat the air that much around the focal point.
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Total Solar Eclipse 2017

05 Sep 2017 03:50

midtskogen wrote:
Without eye protection there's not much to be seen during a partial eclipse.  So if people hear that there is an eclipse and they don't have filters or glasses and really want to see it, it's understandable that they're told not even to try have a look.  The school's fault in your example is not keeping the children in, but failing to provide the means to observe it.

EDIT: As for damaging telescopes and cameras, you need to think of where the focal point is - in particular if it's on your retina or camera sensor.  A narrow view (and sometimes even a wide view) projected on the sensor will permanently damage it.  It's important to have in mind for video cameras or DSLR's with live view when the sensor is exposed for an extended time.

I forgot to point away my 1000 mm after totality in Madras, so for perhaps one minute it was directly pointed to the sun, but there was little to worry about really, since the mirror was directing the focus out of the viewfinder and into thin air, and 1% sunlight wont heat the air that much around the focal point.

Yes, I even get nervous about doing UV photography because I have heard UV light can bleach the sensor (at long exposures which are necessary to capture UV images.)  Sounds like from the way you described it that sunlight is more of a danger with mirrorless cameras (I have both but am now using the mirrorless camera more.)

Yes, the school could've given a real-life lesson about science in the field and they lost the opportunity, especially sad since so many children were curious about the eclipse.
I had a rather annoying interaction on Twitter with someone who purported to be a police officer who said it was wrong for me to encourage people to look at the eclipse.  He said that if I lived in his county he would have me arrested and I would spend the entire time of the eclipse in a cell for my own good and for the safety of others that I might have "endangered" by encouraging them to see the eclipse and not to be afraid of it.
It's ridiculous that this is the state of affairs we are coming to.  I can't even look at the stars through my telescope or photograph them outside of my suburban house without getting questioned about what I am doing although it's easily obvious to anyone who can see the telescope.  So now I don't even bother doing any of that near my regular home and just do it during my long weekends and vacations to my summer home in the Poconos where I have the privacy of 2 acres of land and a high balcony to see over the trees (where I am this long weekend and for most of the week.)
 
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Total Solar Eclipse 2017

05 Sep 2017 04:27

A-L-E-X wrote:
Source of the post I looked at a 70% partial eclipse just with sunglasses

It would be fine for a few seconds -- just like looking without sunglasses -- but for extended solar viewing all they do is provide a false sense of security.  They diminish the brightness over visible wavelengths enough to reduce your instinct to look away, even as your retinal cells are being burned by the infrared, which sunglasses do not sufficiently block. It is correct that you do not feel retinal damage as it happens, and often it is not apparent until later, usually the next morning.

If you didn't feel any pain or notice changes in your vision by the next day, you probably escaped any permanent damage (only an optometrist could tell you for sure), but people have damaged their eyes by doing that and I sincerely hope you do not encourage anyone else to try it.  

Surprisingly, viewing through thick cloud with binoculars is safer than viewing through sunglasses, since the cloud droplets scatter or absorb all wavelengths more equally.  But I still don't recommend it, because if you misjudge it, you won't know until later.
 
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Total Solar Eclipse 2017

05 Sep 2017 05:20

Watsisname wrote:
A-L-E-X wrote:
Source of the post I looked at a 70% partial eclipse just with sunglasses

It would be fine for a few seconds -- just like looking without sunglasses -- but for extended solar viewing all they do is provide a false sense of security.  They diminish the brightness over visible wavelengths enough to reduce your instinct to look away, even as your retinal cells are being burned by the infrared, which sunglasses do not sufficiently block. It is correct that you do not feel retinal damage as it happens, and often it is not apparent until later, usually the next morning.

If you didn't feel any pain or notice changes in your vision by the next day, you probably escaped any permanent damage (only an optometrist could tell you for sure), but people have damaged their eyes by doing that and I sincerely hope you do not encourage anyone else to try it.  

Surprisingly, viewing through thick cloud with binoculars is safer than viewing through sunglasses, since the cloud droplets scatter or absorb all wavelengths more equally.  But I still don't recommend it, because if you misjudge it, you won't know until later.

Thanks Wat, I was doing different things at different times.  I had a solar filter on me that I use with my telescope so for some of the time I was just holding the solar filter up in front of my eyes to see it more clearly.  When the sky became dark I switched to sunglasses because I could not see clearly through the solar filter since it was so dark.  We had some clouds that were passing through so that made it darker (but did not cover the sun, more like it was visible through it as if looking through smoked or frosted glass.)
 
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Total Solar Eclipse 2017

05 Sep 2017 11:17

Photos of Cameras and Lenses That Got Destroyed by the Solar Eclipse.

it seems odd that a 20 mm can suffer that kind of damage, but perhaps the focus was off so light from infinity had its focal point too close to the iris.
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Total Solar Eclipse 2017

05 Sep 2017 13:06

Wow thats crazy so maybe what that guy said about hundreds of people going to hospitals because of the eclipse was accurate?
 
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Total Solar Eclipse 2017

05 Sep 2017 13:43

midtskogen, when I first got my camera I took unprotected pictures of the sun during sunset, it never heated up enough to melt like that and it sat facing the sun for a good hour or two.

These were the kinds of pictures I was taking, I was using my welding glass to line up shots but the camera sat unprotected
► Show Spoiler


When it came to the eclipse though, I had my camera constantly covered when not using it.

Here are two pictures from an old point and shoot showing my camera during the eclipse
Threw a shirt over it for a shade spot so I could look through the viewfinder
Image

And when not taking pictures covered the whole thing
Image
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Total Solar Eclipse 2017

05 Sep 2017 14:07

Wow it looks like you were in some tropical paradise in one of those pictures
 
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Total Solar Eclipse 2017

05 Sep 2017 14:09

A-L-E-X, I lived in South Florida from 2007 through 2016.
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Total Solar Eclipse 2017

05 Sep 2017 14:16

Wow you must be watching the track of this monstrous storm with extra attention :(

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