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Rental camera gear destroyed by the 2017 eclipse (lensrentals.com)
599 points by blueintegral on Sept 2, 2017 | hide | past | web | favorite | 153 comments

It's a shame that Lens Rentals had to suffer such material loss, but that report is absolute gold-plated first-hand evidence for my perennial debates with other photographers who insist that they don't need Solar protection for eclipses.

"But I took a landscape shot at midday with the Sun in frame and it didn't melt my sensor". The difference being the length of exposure and the concentrations of energy.

Just to clarify, there’s no concentration of energy involved with the eclipse itself. The concentration involved is no different than setting a leaf on fire with a magnifying glass on a regular day.

The sun isn’t a garden hose. Putting something in front of it doesn’t make the edges more intense.

There kind of is, because it's darker when the sun is partially covered, so you'll use a larger aperture or longer exposure than you would normally. This is also why it's more dangerous to look at the sun during an eclipse than it is normally: your iris opens wider during an eclipse because it's not as bright.

I think you misunderstood his point, which was: there is no more energy coming from the sun at any given point during the eclipse than in a clear day. The sun isn't "sending" more energy on the path that aren't blocked, nor is the energy blocked going around the obstacle and concentrating on the areas still visibles.

The reason for the damage is entirely due to the receiver behaving/being differently, be it your eyes or your camera, because they get tricked into thinking it's dark and they act like it, being much more receptive and then overwhelmed.

"tricked into thinking it's dark" is kind of misleading, because it is in fact darker, but for some reason unknown to me there the energy from the sun harms you as much. I thought the issue with looking at its sun was its brightness, but i guess it isn't?

During a partial eclipse, part of the sun is hidden behind the moon. So the overall amount of light reaching the ground around you is indeed less, in direct proportion to the amount of sun that is eclipsed.

For example, if 90% of the sun is covered by the moon, then only 10% of the usual amount of sunlight will light up the area around you. So it is quite a bit darker than usual.

However, the portion of the sun that is still visible is just as bright as it would be on any other similar day. If you stare at that remaining portion of the sun, or aim a camera at it, it will cause the same damage as it would any other time, only in a smaller crescent-shaped area instead of a full circle.

The danger to your eyes is even greater, because the overall darkness tricks your irises into opening up wider and letting even more light in than usual.

You're pretty unlikely to stare at the sun for 30 seconds on a normal day. But people do that during a partial eclipse, and that's the problem. Similarly, people don't usually aim their cameras directly at the sun with the lens wide open and no solar filter - except during an eclipse.

A total eclipse is quite a different thing, of course. During totality, the sun's bright photosphere is completely hidden, and only the much fainter corona is visible. This is only about as bright as a full moon, and it's perfectly safe to take pictures with any lens, and to observe directly with the naked eye - even with binoculars.

So I could shine a flashlight into my eyes while looking at the eclipse, and I'd be ok?

That's one of the best explanations I heard about why and how the eye damage can occur. I'm curious how far can you carry that reasoning: If 99.9999999% of the sun were covered during a partial eclipse (down to a single stream of photons), does it damage one single rod on my retina as opposed to a crescent-shaped region? I'm guessing that a single stream of photons from the sun doesn't have enough energy to do any damage.

Now that is an interesting question!

Anecdotally, I viewed the 1979 total eclipse with binoculars (and no filters), and at the end of totality I continued to look through them for a few seconds to see the diamond ring and Baily's beads.

It didn't harm my vision at all, even though there was some fair amount of direct sunlight coming through by then. But it was only a few seconds. The duration of sun exposure certainly is a factor.

The issue is how much light gets focused onto a small area of your retina. When the sun is partially eclipsed, the darkness makes your iris open up to let more light in. That then focuses more light from the visible part of the sun onto the same area of retina.

Your iris reacts to visible wavelengths and not ultraviolet wavelengths. So your iris is open much wider than it ought to be given the amount of UV present (especially given that UV is much more damaging than visible). If you see what I mean :)

It is brightness, but brightness at a single focused point, not total brightness.

> because they get tricked into thinking it's dark and they act like it

This is a really bad example :DDD

I don't think that is totally true for human eye. You can test it by putting a LED spotlight in front of you at night, and have someone else check your pupil before and after you turn on the LED (And remember test it in different distances).

Camera works differently, they have multiple ways (Metering Modes) to test the brightness of a scene. So how it work will depends on the selected Metering Mode.

And camera can collect more light by letting light keep entering the light sensor for longer time. Plus, bigger lens can also collect more light, some people may even mount their camera on a telescope, thus more light entering. So maybe this is the physical reason why so many gears got destroyed?

I understood the point just fine. My point is that there is a greater concentration of energy which is what causes damage, it just happens in the optics rather than at the source.

i was always wondering how a pin hole protects you, and i mean im sure i could have looked it up but just, really wasnt important. dude that tid bit made my day - the more you know

Dingaling is talking about the light being concentrated on certain areas of the sensor. Because the total/average brightness is low, the exposure ends up being much longer then at normal conditions, causing damage to the areas where the light is concentrated. Under normal conditions, the light will be less concentrated on certain spots, so even though there is much more light in total, the camera will choose an appropriate exposure that will prevent damage to the sensor.

You'd have to be incompetent to trust autoexposure during an eclipse.

> The concentration involved is no different than setting a leaf on fire with a magnifying glass on a regular day.

That's what they're saying. Zooming in on the sun vs the sun happening to be in-frame.

Are you saying zooming in on the sun makes damage more likely?

Wouldn't zooming in spread the sun's energy across more of the sensor? Same energy, larger area = less intensity.

The irradiance is determined by the aperture, which is measured relative to the focal length. So with e.g. f/2 you get the same heating of a given area of the sensor regardless of the focal length (i.e. "zoom").

Put differently, longer lenses typically also have bigger absolute apertures, collecting incident light from a larger cross-section. This compensates for the fact that a given solid angle of incident light is spread over a larger area of the sensor.

They have an in-house repair shop that dealt with most or all of it, and they charge the customer for the cost of the repair. From the comments the fact that they don't gouge on repairs is one reason some folks use them.

How do you fix a burnt cmos sensor? I feel like canon would charge you near enough the full replacement price.

I'd imagine it's a fairly common replacement. I've seen event photographers do it quite a few times putting their cameras near lasers.

I'm only a reluctant amateur photographer, but my understanding is that damaged sensors cannot be repaired, and that manufacturers will quote repair costs totalling or exceeding the cost of an entirely new camera.

A quick search online reveals plenty of sources of replacement sensors, at a fraction of the cost of the complete camera.

There do seem to be people selling 7d mark ii cmos sensors for ~$300, while a new body would cost ~$1100.

Someone posted a video of replacing the sensor on the old 7d (https://www.youtube.com/watch?v=udonzfGdW0Y)

Seems it eventually worked for him, after several attempts to adjust the position to get correct focus, but if you read the comments on the video there are many people who've messed up their camera trying to do this.

Might be fun to try though.

They might send that back to the manufacturer to fix.

In the Reddit thread, they talked about replacing the aperture module for some of the lenses; that's just a simple swap, along with cleaning the adjacent elements.

You fix it yourself, most likely using a sensor from another broken camera.

I wish the blog post had talked more about that. I'm curious about their repair process. What capabilities do they have in house? Can they replace a broken sensor?

They blog a lot about their repairs process in general. It's primarily mechanical damage to lenses they appear to normally deal in - the focusing rings, aperture mechanisms or realigning optical elements dislodged by drops and so on. An embedded CCD/CMOS sensor is probably a full logic board replacement I'd assume, as opposed to some kind of sensor only replacement, given it's almost always soldered on.

I know about 12 years ago I blew the firewire connection on my video camera (Canon xm2), and to fix it they would have to replace the full board.

So I feel like they don't make them repairable.

There are a lot of things that a professional repair shop focused on a particular type of equipment may be able to do that aren't practical for anyone else - including manufacturer repair facilities. Louis Rossman is a bit entertaining on this: https://m.youtube.com/watch?v=ocF_hrr83Oc

Yet with a heat gun its an easy fix.

It depends on their expertise

Yup, it all came down to how long the camera was pointed at the sun. I took a bunch of photos of the eclipse including this HDR shot with a Leica 280mm lens and Sony A7R with no filter whatsoever & without any damage to my lens or camera. The thing is, it took seconds to take and I made sure the camera was only pointed at the sun for brief moments:


I'm assuming the damage Lens Rentals saw was from people who were trying to do time-lapse.

Off topic, but I think here's another image of the same airplane, also taken in Idaho: https://www.reddit.com/r/aviation/comments/6v62nl/plane_cros...

That turned out to be a fake.


Oh man that's hilarious considering this: https://petapixel.com/2016/01/29/nikon-awards-prize-to-badly...

I was in North Eastern Idaho and there is a similar looking contrail visible in my wide angle shots at totality so if the point of image capture happened to be just right it would be possible to have it in the frame with the sun.

That one would have been taken about 15 miles or so to the southwest of my location.

You can torch your sensor in seconds:


At Lick Observatory, they close the slit in the roof before repositioning during daytime observation (yes, that is a thing) to avoid even the chance of running into Mr. Sun.

Yeah, if you use a super-telephoto lens, then take your camera body off and change the focal point so that you are using your lens as a magnifying glass like they did in the video. No doubt. For the rest of the sane world; however, it's not quite that risky. For reference, that Leica I used in my shot is a one of a kind as it was the first lens to roll off the line when Leitz branding was changed to Leica & estimated to be worth between $12,000 to $22,000. I wouldn't have risked it if there was any risk whatsoever.

No, it is the opposite. A 50mm f/1.4 lens focus the light and the heath much more than a 300mm f/5.6. You were quite lucky with your camera I guess.


The flux for the sun on the sensor/film/whatever is:

    Φ/4α² * 1/A²
Where Φ is the sun flux at the surface of the earth, and α is the angular diameter of the sun. A is the f-number of the lens, the only variable in this equation. It doesn't depend on focal length.

The total power over the film is:

    Φ/4πα * f²/A²
which does depend on focal length, but that is usually not the determinant factor, as for surface burns the damage depends mostly on the flux.

Surface damage mostly depends on the power density, not on total power, so it depends mostly on the aperture, not on the focal length. This makes longer focal lengths safer to point at the sun because they are slower lenses. They are also safer if you don't explicitly point them at the sun because they are less likely to catch the sun in the smaller field of view.

Burned shutter cloths on Leica M series cameras with wide angle lenses is a real problem that can happen simply if you leave the camera without a lens cap lying on a table. This is less of a problem on most other cameras, as they use metal shutter curtains.

I wonder if that guy damaged his lens while making that. That lens looks similar to one of the damaged ones in the article.

To satisfy your curiosity, he did not. The lens was borrowed from his workplace (a camera store) for the purpose of the video, and was returned unharmed.

The creator of that video hangs around on /r/photography, his comment is here: https://www.reddit.com/r/photography/comments/6xg8a7/lens_re...

> And of the things returned, we were equally impressed with our customer-base, and their guilt and owning up to the damage.

I thought the renters would be paying for it?

They still probably lose out on some revenue until a replacement is in stock. Having a working lens is always better for business than getting reimbursed to buy a replacement lens. (That's the nature of the business, though.)

LensRentals do all possible repairs internally, so I suspect that the downtime on an expensive lens like that is minimal if possible. Roger mentioned on the photography subreddit that the aperture replacement was a $200 part and 3 to 4 hours -- it only took so long because it was that tech's first time replacing that part.


He mentions in the article they rented out “thousands” of lenses. I’m guessing the few lenses they have to repair because of this is barely over their normal repair load.

The renters are paying for it. Next sentence:

> Unfortunately, these types of damage are considered neglect

Still, lots of people might feign ignorance.

You can feign ignorance. It doesn't change the fact that the lens has a burn hole on it now.

Deny, deny, deny.

Ah, yes, the Shaggy defense [1]. It's is rarely is successful in practice though.

[1] https://en.wikipedia.org/wiki/Shaggy_defense

It's like denying you murdered somebody when you sent the police the murder weapon with your fingerprints in the victim's blood. Unless you're OJ Simpson, you're going to jail.

lens? what lens?

Presumably the rental place isn't planning to just eat the loss. They have the renters' credit card numbers...

When you hire a lens, you're contractually and personally on the hook for anything not insured.

So yes, somebody owes LR a considerable amount of money for repairing or replacing that £11,000 600mm lens.

The admin of dealing with this crap is built into the rental price. A well looked after lens doesn't depreciate fast.

Worth noting that on the 600mm with melted iris, the user did use a solar filter.

Unfortunately for the lens, the 600mm lens's drop-in filter slot is behind the iris. So the camera was fine, the lens not so much.


Why do they even make a drop in filter rated for the sun, if it's going to damage the lens?

What use could you make of this filter?

There is a drop in filter holder that takes 52mm filters designed to screw on to the front of lenses.

(For those unfamiliar - it works this way because the objective element of this lens is far larger than anyone makes filters for. 52mm is a very common diameter, so placing a drop-in mount further along in the focal path means you can use a wide range of filters with minimal cost and inconvenience, and to identical effect - except, of course, in the rare case where you have enough energy coming down the barrel to damage the iris.)

hey astronomy was a wicked hard class and i still dont get it, so maybe this will be a very expensive lesson for them. sadly it probably wont be the right one but that is life. you know that there had to be a couple of smug asshats that were brought down a peg, thats pretty funny. I missed the eclipse.

At one point during the eclipse I used a pair of binoculars to project an image of the sun onto the ground. Of course, it was a double image, so to fix that I covered one of the eyepieces with my hand. It took about three seconds for the pain to register. Hard to say which hurt more: the small, first-degree burn on my palm or the rest of me from kicking myself afterwards.

Should have covered the intake side.

Now you tell me! ;-)

Well, you're good for the next one.

only if you live to 300!

? There's another total eclipse coming through North America in 2024. Passes right over my city, hurrah.

What state is hurrah in?

Even so the whole idea of naked binoculars pointing at the sun sounds dangerous.

I think my favorite part of this article is how the author is so understanding and positive about his users. I think if I had rented out cameras to people, told them not to point it at the eclipse, and then got a bunch of damaged cameras back, I'd be pissed. In fact, I might have choice words for those customers.

I think there's a lesson here in targeting inexperienced consumers. Perhaps a good preventative measure would have been handing out protective lenses before the eclipse so that customers would have really had to try to mess it up.

Why would he be angry? The customers are paying for the damage.

There's still a potential opportunity cost from temporarily not having those damaged items in stock.

IANAPhotographer, but many other rental businesses (cars, boats, bicycles, etc.) make lots of money on overcharging for repair/theft. It wouldn't shock me to learn that camera rentals are the same.

> and then got a bunch of damaged cameras back, I'd be pissed

It might not be good business to express that in a blog post

Yeah, got to remain positive and cheery and use it as a positive "learning experience".

It could also be that these people renting out camera equipment are guaranteed to have seen much worse damage, expected worse damage - and that in this instance - the customers appears to have taken responsibility for the damage to an unusual extent.

There's certainly enough positive surprises in the above to warrant an upbeat post, one that can also be used to educate about how camera systems can be damaged, and the limits of their insurance.

Ha ha I was thinking the same thing. Wouldn't surprise me if they had some of the article written / drafted in advance. Excellent PR and free advertising.

> .... I'd be pissed .... choice words for those customers.

Then clearly this is the wrong business for you.

Dealing with stupid customers simply comes with the territory.

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.

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.

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.

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

I am completely battled as you too...

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.

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:


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."

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).

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


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

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.

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?

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

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

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.

Those were some expensive mistakes. Some of the gear mentioned: Canon C300 Mark II ($9,999) and Canon 600mm f/4L IS II USM ($11,499).

Nobody is going to throw that gear away. They'll replace the diaphragms but the glass and body should be fine.

No, but expensive things have expensive parts/repairs. Just pointing out for those not in the field that this was pro level gear.

Interesting! My assumption is that this could not happen with a phone camera though, correct? Because then one would think just leaving one's phone face down on the table in sunlight would ruin it.

The sun would have to be dead center middle so it's probably unlikely. The lenses on the fancy cameras definitely make it a far worse problem for them vs our phone cameras though.

An iphone 6 camera only costs 5$ and is easy to replace(with a screw driver and spudger (maybe an igizmo) most hacker news people likely wouldn't have issues.), so it's not the end of the world (source:I repair phones)

Most people don't mount their cell phones to tripods or celestial tracking mounts so there's enough movement it would never be an issue. It would be interesting to mount one to a celestial tracking mount and see what happens. Honestly, I've got some old cell phones laying around here and might just give that a try.

That would be really cool to see! /u/tzs posted some links, so it looks like people a somewhat unsure. I'm guessing that if the sun is well tracked in the center for long enough that it would damage the lens. I guess we don't have a ton of hard data for it.

So I've photographed lasers a bunch and burned a few sensors, I guess I should toss in my experience. As far as I can tell, it really depends on the specific phone that you're using, and also the damage is usually fairly minimal. I've damaged fancy sensors with lasers and they almost always have major problems afterwards, but for years I used a phone with a very severe amount of laser damage to the sensor and the photos were quite good and the damage was barely noticeable (as a series of black lines on the image.) There was no damage to the lens.

I also doubt it would be the lens damaged in the case of a smartphone. The lenses are built to take a tremendous amount of abuse and almost certainly would be fine. The sensors are by far the more fragile component.

The most common expert opinion seems to be that photographing the Sun with a smartphone camera won't damage it. Here's a NASA document on this: [1]

A Chicago Tribune story [2] cited the WSJ [3] saying that Apple said that eclipse photography would not hurt an iPhone.

Forbes says that recent generations of iPhone have sensors and lenses just big enough to cause damage if you point them at the Sun for more than a couple seconds, but that selfies that include the Sun are fine because the front camera and sensor are small [4].

[1] https://eclipse2017.nasa.gov/sites/default/files/Photographi...

[2] http://www.chicagotribune.com/bluesky/originals/ct-bsi-eclip...

[3] https://www.wsj.com/articles/yes-your-iphone-can-photograph-...

[4] https://www.forbes.com/sites/anthonykarcz/2017/08/18/dont-le...

>Forbes says that recent generations of iPhone have sensors and lenses just big enough to cause damage if you point them at the Sun for more than a couple seconds, but that selfies that include the Sun are fine because the front camera and sensor are small [4].

i don't buy it. phones get their rear cameras pointed towards to the sun all the time. all it takes is you putting the phone on its back out in the sun. you'd be hearing thousands of reports iphone cameras mysteriously getting damaaged. not to mention that it's not really forbes saying that, it's some blogger that forbes sold its name to (a practice they're infamous for)

A thread higher up discusses the damage being related to the aperture size - phones have a tiny aperture.

Not really, the light flux is not really related to the physical aperture (diameter of the lens), but rather to the f-number of the lens (what photographers usually call "aperture" is in fact the f-number, focal length divided by lens aperture), an iPhone has an f/1.7 lens. This is an extremely fast lens, faster than any any zoom on a DSLR. Only dedicated prime lenses are faster.

The flux is:

    Φ/4α² * 1/A²
Total energy does depend on actual aperture though. Total power is:

    Φ/4πα * D²
Where D is a diameter of the lens.

As a first approximation, the sensor can support a certain flux, but once that regime is exceeded the damage is proportional to the energy, not to the flux. So if we talk about the regime where the sensor is not destroyed, flux is the relevant metric, but a larger lens will likely cause more damage once damage actually occurs.

This is just theoretical pontification, but I think there is a respect in which size matters: heat dissipation. Suppose you have a sensor laminated to a heat sink. If you apply some flux density (power per unit area) to a very small area (as would happen with a phone camera), you can dissipate heat in three dimensions: back toward the heat sink and to the sides through the rest of the sensor. If, in contrast, you apply the same flux density to a large area, the edge effects matter less and you approach the limit where heat only dissipates straight back. This could have a dramatic effect on the temperature.

A similar effect happens in the kitchen. It's very easy to burn yourself by touching a large hot surface, but it's much harder to burn yourself by touching a hot pointy thing.

Anyone who doesn't take their glasses off and look at the total eclipse for a moment when the sun is completely covered, is missing out. It's a beautiful sight.

Caution is needed of course. Get ready to put those glasses back on any moment now!

Incredible hues and glow and the surrounding twilight. Can't see any of that with glasses on. At totality, sneak a peek with your naked eyes, it's fine.

Same for camera equipment, it's the setting up and pointing the camera at sun before the eclipse that does the damage. Keep lens cap on until last moment, then take off, and nothing will happen to camera. I've done it at two eclipse festivals, no clouds, didn't even use ND filter! Cameras and eyes fine.

Since others are posting their images figured I'd pitch in: https://g2.img-dpreview.com/8D7D9675C7AE4E6EAEF707CB4AEABB2F... Canon 100-400 @400mm +1.4x tc, solar filter removed.

I got lucky while testing my camera, which is mounted at prime focus in a refractor scope. I had it in Live View which meant the mirror was up, and I removed the solar filter for just a second.

The camera said "error", turned off, I replaced the solar filter, and it was fine. Much longer, and I'd have had a burn. The telescope really collects and concentrates a ton of light.

According to the thread above, the telescopic lens is safer to use than a shorter one. Only here would someone give a mathematical proof!

No, a slower lens (higher f-number, or, actually, T-number) is safer than a faster lens. It's only a practical accident that a long "telephoto" lens is usually significantly slower than a lens closer to normal for the format (and that the long end of a consumer zoom is usually slower than the wide end). A 600mm f/4 lens is an eye-wateringly expensive hulking monster; a 50mm f/1.8 lens is the proverbial cheap-as-chips (with some exceptions), but will let about 5-6 times the amount of light through to be imaged on the sensor - it'll burn a smaller hole, but do it much more quickly. Should you be able too find a 600mm lens with the same T-number (similar to the f-number, but taking transmissivity losses into account), it'll do the job just as quickly, but much more thoroughly.

Actually, this was a self-built telescope. It was a 3.5" apochromatic 900mm focal length lens adapted to a T-mount.

If you remove the camera, and point the scope at the sun, there's a good sensor-sized beam of intense sunlight at focus.

I can almost feel the LensRental writer's pain of having to write this article without calling a bunch of dumbaxxes dumbaxxes because they are their customers. sigh

Does the eclipse make the sun stronger or something? I've pointed my camera at the sun for all day long taking timelapses and nothing bad happened to it. I guess maybe you need a really hardcore zoom lens to get damage like that...

P.S. Here's the video pointing at the sun all day long: https://youtu.be/HgbG--t3Bd8

On the day of this event I was at the hospital and everyone just used X-ray films. They work well enough. I also did try a pair of sunglasses, and I could last maybe for a second or two. I am not sure if my eye sights have been damaged since then. I hope not... I repeated a few times but all done around 1pm-ish in NY, so not at peak. It was more like looking directly at the sun during noon everyday.

I wonder, did they include a solar filter with all their rentals? If not, I wonder if that would have saved everyone some trouble.

Probably not, they are expensive, fragile and have very limited utility outside a major eclipse event.


Most people don't buy expensive screw-on types like these for a one-time event. You buy some solar filter film and fabricate yourself a lens cover out of cardboard for about $10.

Luckily I bought mine from Amazon and due to the ISO certification debacle they refunded my money and allowed me to keep it.

I was shooting with a d800 200mm lens, no filter. There is no visible sensor damage, both when examining images and the sensor itself. I have to check out the lens. I left it on the sun for a good 20 minutes in live view but there doesn't seem to be any damage. Thoughts?

Were you using a motorized tripod set to track the sun? I would guess that was the cause of the most extreme damage.

It is not just at the focal point but

multilayered lenses can be destroyed as the expand and contract and heat is emminated from the join and also

Any lense with coatings to correct for chromatic abberation, the coatings get destroyed on the surface of the lenses just by being pointed at the sun.

A lot of phone cameras seem to have come through (apparently) unscathed. Both pictures and video. Too small a collector/concentrator, or enough shaking because hand-held to keep the focal point moving?

I used a Canon 80D with a EF-S 55-250mm lens and a solar filter film over the lens. My camera was fine.


Taken in rural Oregon (just two shots I selected at random for this post)

The amusing bit is at the end, where the author tacitly admits that their add-on camera insurance is somewhat crap. Someone who damaged a rental camera by pointing it at the eclipse would, ironically, have been better off if they then proceeded to "accidentally" drop the camera from a height onto concrete:

Unfortunately, these types of damage are considered neglect, as warnings were given out to customers before the solar eclipse. Our LensCap insurance plan, which can be added to rentals for a small nominal fee, does not protect from neglect but is an excellent tool for those who are worried about their rental and want to protect themselves from any accidental damage.

(but perhaps not really - there are enough wiggle words in that policy that I wonder if they ever pay out on expensive damage at all: https://help.lensrentals.com/26475-damage-lenscap-protection... )

Intentionally using gear inappropriately in ways that are highly likely to result in damage isn't what insurance is for. Reasonable guidelines around what insurance will cover keeps it cheaper for everyone.

Especially with an explicit warning sent out about the eclipse.

A camera is repairable, so it's not like they throw out the entire "broken" item. Dropping the camera would have just created a second problem.

It's an interesting line, between accident and neglect. Reading the article, my initial reaction was that it is ridiculous for their insurance to not cover this damage. But yet in general I do enjoy the non-diligent actually retaining some moral hazard. This "absent agency" problem is usually addressed with a deductible, but that still doesn't fully price in the cost of easily-prevented damage.

Recently renting a box truck and not wanting to be on the hook for a $150k piece of capital equipment, I got the damage waiver. But I had wished for a cheaper policy that would have excluded damage from low drive-throughs and parking garages, which presumably makes up the majority of their claims. Alas.

> A camera is repairable, so it's not like they throw out the entire "broken" item. Dropping the camera would have just created a second problem.

That's the irony about insurance that I was pointing out. The much worse situation would have been covered.

Erm, do you mean "worse" as in more money to repair a dropped camera (new body, realigning lenses, etc), or worse if there were two separate problems? In the second case, I'm guessing the repair technician would say "In addition to being dropped, the image sensor is also burnt", and the camera shop would say "okay, looks like you burnt the sensor with the eclipse, and then most likely dropped the camera on purpose", and would cover nothing.

In general, insurance relies heavily on intent. Intentionally breaking the camera on the ground would not be covered. Gross negligence (like ignoring the warning of the camera shop and proceeding to burn the sensor) is interesting because to the person doing it it feels like an accident, yet to most everyone else it feels like they didn't try hard enough not to.

They were very upfront about the fact that eclipse damage would not be covered.

They also don’t cover damage from Color Runs, and they’re upfront about that too.

Landing on concrete isn't likely to melt the sensor though.

"Oops, dropped it from the building from which I was shooting the eclipse, it fell 200m on concrete" – hands in pile of plastic.

(Although this would be a very unfair move)

many of those depicted lenses and camera bodies have metal exteriors/frames. ignoring the glass, they'd probably still be in a single piece after 200m. and without any obviously melted bits.

Then walk with them over a road in NYC and accidentally drop them so a 60t truck drives over them. Should thoroughly remove any and all evidence.

Upvoting just for the phrase "wiggle words".

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