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Comment by jmiserez | Hacker News Reader

Now imagine that kind of damage being done to your eyes.

It hurts just thinking about it, yet some people don’t seem to really believe the warnings.

I'd argue this is slightly worse because the cameras have higher magnification lenses* vs our naked eye. This might be more akin to looking into a telescope with your eyes.

Edit: To elaborate - Higher magnification lenses (depending on the camera lens used of course)

Edit 1: - /u/corndoge Suggests that people may take this the wrong way. I mean to say in the amount of physical damage it's worse for camera's because of the extra (and typically higher magnification lens). I don't mean that a burnt camera is worse then a burnt eye - I'd rather anybody loose tons of $$$ for a camera then have eye damage.

Our naked eye has a lens too.

But it’s not a 600mm tele, so the actual area of burn damage is going to be smaller. You’ll still have a blind spot in the center of your field of view, but not the whole eye. Still, I imagine it’s quite a disability either way.

Info about the different mechanisms of eye damage due to bright light:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3144654/

This is well written and accessible article. Thanks for the link. One of the best short lay descriptions of light that I have come across: "Light is a form of electromagnetic energy. Electromagnetic radiation has a dual wave-particle nature. When light is absorbed by a photoreceptor, its particle nature is important."

Could somebody tell me why this comment is being downvoted? I didn't feel like I was being rude (I'm sorry if I was), and I'm pretty sure it's a correct statement.

Our eyes have lenses but as /u/jmiserez said the lenses in the cameras lenses magnify it far more. It'd be like us looking into a telescope looking at the sun (Obviously depends on which camera lens you use).

Edit: I edited the main comment to explain that the difference is that camera's typically have higher magnification lens then our eyes.

I am completely battled as you too...

probably because you suggested damage to a camera is worse than damage to a human eye in the first sentence and hn is full of reactionary children

Focal length has nothing to do with it, in fact, longer focal lengths are generally safer because lenses are slower. Aperture is what matters, lenses gather much more light than our bare eyes.

Is the issue aperture or aperture over focal length? The actual aperture (squared) determines how much solar energy you are gathering. The aperture over focal length (again squared) determines the energy per surface unit.

I'm not sure which is more damaging here.

It's not so much about the magnification as it is about the light-gathering surface. The human eye has a relatively small aperture; a professional camera lens has a huge aperture, and it focuses all the light from there onto the camera sensor.

Higher magnification actually makes it slightly safer, because the image of the sun ends up magnified and spread out over a larger part of the sensor. Low magnification means it all goes to one point.

I was recently party to a conversation where someone was saying that they couldn't find eclipse glasses in the store, so they had to "look through a Ritz cracker, like they said on the news". I figured they meant use it as a pinhole lens, but they continued saying that the sun was still pretty bright even using the cracker. I didn't want to blow up the spot by clarifying/correcting (and it's not like I could have prevented their eye damage after the fact), but I definitely got the sense they were looking directly through the holes in the cracker. This person is an educated white-collar professional.

This is amazing!, while I would never advise this as an option, it probably would be fine

Erm, your comment makes me think you didn't quite get what I was saying.

Using the holes in a Ritz cracker as a pinhole lens to focus the sun on a sheet of paper seems eminently fine, as you're only subtracting sun from the case of looking at the paper outside (as opposed to using a glass lens to image the sun, which gathers light from more angles and concentrates it). It seems like poorer optical quality given its thickness, but could be handy if you don't have access to a piece of paper and a staple, or if you're a clickbait journalist trying to entertain a dying audience.

Looking through the hole is idiotic. It'll cut down on some of the light sure, but nowhere near the attenuation required - a quick search shows a #13 welding shade lets through about 10^-5 of the light.

I just googled for reports on the eclipse's aftermath the other day, and there seemed to be noting about widespread eye damage (or I did not search hard enough).

It was interesting how most of the post-eclipse reporting was hijacked by a certain politician not wearing his glasses (probably he only looked for a split second anyway). Anyway, this eclipsed (sorry) any reports about the actual event, which must have been one of the largest events in history based on the number of spectators (I saw estimates of 20 million people across the US).

Just like the picture of the pope not smiling for a moment.

Or when the Queen of England is at an event and doesn't smile for a moment.

Or "woman wears shoes"

or "look at the number of people in this place compared to this other picture where the numbers were different at a different time of the day"

it's all so tiresome

> Lawsuit: Amazon sold eclipse glasses that cause "permanent" blindness"

https://arstechnica.com/tech-policy/2017/08/lawsuit-amazon-s...

Apples and oranges. Eyes are wet, lenses dry. Eyes would never catch fire. Boil maybe. The damage to eyes happens at far lower temps/times and, as many have found the hard way, it doesnt even hurt.

FWIW me and my coworkers looked at the eclipse with no protection (it was too foggy to use our pinhole cameras). I didn't develop any vision issues, and I don't think the others did either.

Of course it depends on lots of factors, but to see the equivalent eye damage, do an image search for “solar retinopathy”. It’s not just theoretical.

Absolutely, I know it's not just a myth. It's just that whether you need eclipse glasses is more nuanced than "always wear them." If you're going to stare at an eclipse for multiple seconds on a cloudless day you're probably going to be in for a world of hurt.

Staring at the Sun is bad, no matter when you do it. The Sun emits no extra photons during an eclipse. Your pupils do expand due to physiological responses of the decreased light, however.

In San Francisco the eclipse was only partial and behind a cloud of fog. In that case looking at it's no worse than looking at the sun behind a cloud on a non-eclipse day.

Watch out over the next couple of months, and don't rub your eyes if you think they feel like they have sand in them, just go to the doctor. There was a reddit thread about people who damaged eyes after looking at an eclipse, and several of them showed effects later.

It's funny that after hearing dozens of warnings about how looking at the sun will permanently hurt your eyesight, people GO and actually LOOK at the sun without protection. I suppose stupidity has no limits?

Same here. So much fog cover in SF that you couldn’t even see it through eclipse glasses. Normal sunglasses were just perfect and naked eye was okay for a few seconds at a time.

I mostly looked at it through the display on my camera though. Didn’t even cross my mind it could cause damage. Luckily it didn’t

NASA says it's safe - for the brief period of totality.

  During the short time when the moon completely obscures
  the sun – known as the period of totality – it is safe
  to look directly at the star

https://www.nasa.gov/content/eye-safety-during-a-total-solar...

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