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Two Photographers Unknowingly Shot the Same Millisecond in Time (petapixel.com)
1397 points by shawndumas on Mar 8, 2018 | hide | past | web | favorite | 215 comments

This has always been one of my favorite photographic coincidences. https://calculatedimages.blogspot.com/2013/05/3d-lightning.h...

The result is a pretty cool 3d photo of lightning.

It's kind of amusing that in the 3D model the lightning bolt's shadow is visible, as if it were an obstruction rather than a light source.

I think everyone who visualizes laser beams, light rays, etc. forgets to set the no_shadow property at first, and then chuckles upon seeing the result.

This article is far more amazing than the OP's link.

It's a matter of opinion but I strongly disagree, the brief existence of a lightning bolt is going to force the exact same moment out of two photographers, and they were shot from two wildly different locations. The analysis was fairly cool but I see cool things every day.

The sheer improbability of two photographers capturing the same wave in the exact same way from meters apart and publishing the same shot is captivating. There are thousands of waves daily, and thousands of interesting places to capture them.

not really. one you setup your tripod there, you are already focusing on the light house... and then when a wave is crashing in, you just hold down the shutter for a few burst shots... very easy to replicate the same shot...

say if it was a photo group... then the chance of same shot being outputted is even greater

Google Chrome thinks this site is dangerous:

    Your connection is not private
    Attackers might be trying to steal your information
    from calculatedimages.blogspot.com (for example,
    passwords, messages, or credit cards). Learn more
The message details continues to say that

> You cannot visit calculatedimages.blogspot.com right now because the website uses HSTS. Network errors and attacks are usually temporary, so this page will probably work later.

Are you sure you don't have a configuration error on your end? Time set correctly etc?

Maybe some MITM on your network? Dodgy SSL certs in your OS?

Blogspot is a google operated domain after all.

The certificate is signed by a Google intermediate CA using GlobalSign as the root CA.

I don't use Chrome but I find it hard to believe that Chrome now distrusts Google's own CAs. A user errors seems more likely :)

For the record : those two parts (their CA / own services, and their teams responsible for security) are really well separated and it is not the first time a Google thingy is deemed unsafe by Google security.

Whatever one thinks of Google, it's hard to not agree that they take security very seriously, both internal and external (and project zero is one of the best thing ever).

Personally, I prefer it that way. Better to see "ahah, Google tells me Google is insecure" than allowing something flagged as bad just because it come from the same mothership.

> Whatever one thinks of Google, it's hard to not agree that they take security very seriously

I completely agree. Don’t think I stated otherwise?

Anyway, I find it hard to believe for any browser to untrust Google’s intermediate CA. And more so for Global Sign.

That said I recon that especially if Chrome started distruating Google CA that we all heard about it ;)

Fyi. This is the cert I'm getting: https://imgur.com/a/D1RQ2

That's curious.

I'm getting a different cert at least. No cert errors.

Both certs have same common name, etc. But that's where the similarities end.

This is the cert I'm getting:

Serial number: 4254239493315191306

Validity: Tuesday, 20 February 2018 - Tuesday, 15 May 2018

Public key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

Signature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

No foul play, also managed to get same cert you got (with public key 92 e0 55 f9 af 61 0d 7e 7e db 21 84 d5 dc 59 21...).

Perhaps Google uses multiple certs with same Common Name on different servers. If so, I wonder if there's some security benefit.

Or what could the reason for that be?

I could see rolling N copies out so if you needed to revoke one set, another set could remain functional..

Well it crashed my whole browser (Vivaldi, OSX) after I scrolled a bit, so Chrome has a point I guess.

If the browser crashes when rendering a site is the site dangerous or the browser buggy?

Why not both?

I've experienced that type of issue a couple of times when using antivirus software.

Not nearly as improbable, but one time I was reading the New York Times and happened upon the top picture in this article:


Not only did I find that I was (barely) in the picture, but I had a picture of the photographer either before or after he took that picture (not at the same time, obviously, since I was turned the other way at the time of his picture):


Improbable or not, that's great! Two people taking the same photo with phones seems likely these days, but accidentally discovering a picture of yourself taking a picture of the photographer, published in the NYT, that's an awesome coincidence.

I love how completely and dramatically different those two photos of the same place and time are. The reporter was telling a story of somewhere remote and hard to get to and barely touched by humans. One single sturdy but old Siberian looking truck and a half dozen crazy scientists in front of vast stretches of nothing but snow. And yours is showing a bit more of the day in the life there for humans standing next to an airport. The real dot on the i, and extra minor coincidence is the jet taking off right next to the reporter's head. Both photos are true, and both photos, one could say, give misleading impressions taken only on their own.

It's quite possible I was trying to take a picture of the plane taking off, so that might make that aspect less of a coincidence.

Wow, what was working in Antarctica like?

I was working on a long-duration balloon payload (ANITA-IV), so I was in a hangar much of the time. Since it was summer, it wasn't that cold, but the constant daylight is disorienting. The isolation from the rest of the world is the hardest part, even though at McMurdo, unlike pole, there is (slow) internet all day long.

McMurdo is an interesting place with a lot of fascinating people and the scenery is very beautiful. As our balloon launched pretty quickly after we were ready to launch, I unfortunately didn't get much downtime to do all of the hiking trails and such (but on the plus side, I got to go home earlier).

If you ever get a chance to go (either as a scientist or, possibly more likely for many, as support staff), I highly recommend it.

Maciej Ceglowski wrote about McMurdo:


Always been a dream of mine, sadly I don't think as a lowly French IT person that there is a way for me to have that experience.

Thanks for sharing

Have some growth mindset :)

> France operates two stations in Antarctica: Dumont d’Urville Station, in Adelie Land, and the French-Italian joint Concordia Station.

Dumont d’Urville was built in 1956 on Petrel Island where it houses a maximum of 30 people in winter (about 100 in summer).

Concordia was built in 1997 and is operated year round since 2005. It can house 15 people in winter and 60 people in summer. The inland Concordia Station is re-supplied annually by three ground traverses leaving Cap Prudhomme Station, a small annex station of Dumont d’Urville. In addition, France operates three stations in the Sub-antarctic islands: Crozet, Kerguelen and Amsterdam Islands.


Qualified IT personnel are in demand. If this is something you want to do and you apply yourself towards this goal, I'm sure it's quite achievable.

Depends on what age you are, if you are less than 30 it's not very difficult to get to Dumont d'Urville.

I went to Kerguelen island myself as a sysadmin (14 months, a winterover). I had the choice between Kerguelen, Crozet, New Amsterdam and Dumont d'Urville, I don't regret my choice at all even if Kerguelen lacks the special distinction of being on Antarctica.

The Polar Institute, IPEV, recruits about 10 or so IT-related personnel each year (though only two recruitments are for pure sysadmin types - Kerguelen and Dumont d'Urville) under a civilian service contract. It's worth trying it if you're less than 30.

Otherwise it's going to be difficult, and even more so for Concordia I'm afraid.

I've always been strangely fascinated by Kerguelen. Maybe I should try to figure out if I can justify doing an experiment there...

There's a cosmic rays detector that I was in charge of, even if I have little idea how it works. Apparently, it requires some very toxic gas (I have forgotten its name... something with -fluor- in it maybe?) that has since become forbidden from shipping.

So there are a few spares remaining on the island (forbidden from shipping away anyway) but no legal way to keep operating once they are used up.

Project ice cube seems to always be looking for people to winter over. I suppose the hiking isn't as good then. :)


Since the employment would not be in the US, I'm guessing that no work visa would be required. If you are really interested, I think it would be worth your while to contact them.

I have a friend who sometimes works at Pole, and they apparently do need people to winter over and manage the IT infrastructure. I don't know whether they have citizenship requirements (it's a US-led station), but it's apparently a hard enough position to recruit for (six+ months in the dark) that they might be flexible.

I believe that this is the US Antarctic Program's IT contractor's jobs page: https://ghgcorp.applicantpro.com/jobs/

It looks like they only hire Americans though (probably some requirement imposed on the contractor).

There are of course lots of other contractors for other sorts of jobs.

I had the same thing happen with one of my photos of lightning in London. I actually thought my shot had been ripped off at first glance, then realised it was from a different angle.

Mine: https://www.flickr.com/photos/beechlights/2739042419/in/phot...

Alternative, from the Telegraph: https://www.telegraph.co.uk/news/picturegalleries/earth/2515...

Looks at first sight like much of a bigger coincidence, but given that you probably both used a long shutter speed (yours seems to have been 6s) and selected the nicest of a number of shots, it's not like there are crazy chances against getting two almost identical shots like this.

Oh yeah, I don't deny it isn't insanely improbable. Still, finding same strike in a newspaper, shot from a very similar angle, was quite surprising.

Nice quadruple-negative.

Surprisingly readable!

Actually that could be much more likely if both used automated triggering.

Yep, this is one situation where it's actually reasonable. The fact that they both used automatic triggering, and that took a lot of pictures over the period of the thunderstorm make it realistic. I personally don't believe the man in the article. It's easy to make a second account to pretend to be a different photographer (or have a friend pretend), and equally easy to set up 2 cameras to a trigger. There's a lot of competition in photography now days, so I would not be surprised to discover yet another publicity stunt.

The bolt of lightning is clearly identical, but I'm having a difficult time correlating buildings between the two shots. My guess is they were taken a mile or two apart.

IIRC the other shot is somewhere south of the river. I worked it out at the time. I was near Tower Bridge on the north side.

fwiw, yours is nicer :)

I had a similar thing happen. While browsing Google Maps I found what looked like a poorly cropped version of one of my photos:

My photo: https://www.flickr.com/photos/40423570@N07/35437050686/

Their photo: https://www.google.com/maps/place/Fort+Armistead+Park/@39.20...

However, upon inspection I realized there were differences. It kind of blew my mind that someone had taken a picture of the same sunrise at the same time, from almost the same spot.

>It kind of blew my mind that someone had taken a picture of the same sunrise at the same time, from almost the same spot.

Depends on the spot. I'm sure that, on any given morning, there are probably shots taken in a place like Zabriskie Point that are effectively indistinguishable. (Of course, once there are moving objects in the frame, photos that look identical become much less likely.)

That's true, though this particular spot isn't very popular. Until recently, I'd never seen someone else take a sunrise shot from this particular point of view (the beginning of summer is when the sun is closest to the bridge, and it only rises close enough for a good sunrise photo for around 2 weeks). And when I took my shot, I actually thought I was alone in the park.

I remember going to the tour in Arizona & Utah (Grand Canyon, Monument Valley, Zion Park, etc.) and in every scenic spot there were dozens of people with cameras virtually all the time. And when the sunset came, you had to get the good spots in advance because there were even more people trying to take a good shot. So there probably are hundreds of similar photos of these places out there. Still nothing like seeing it all with your own eyes though :)

This is typical birthday paradox stuff right? The chance that these two photographers would ever snap the same thing at the same time is small, but the chance that any two photographers, anywhere, would do so is, I bet, pretty big (even if you factor in millisecond precision). With photographers being photographers and the internet being the internet, there's also a pretty decent change that they'd find out about it and write a blog post like this, no? :-)

> but the chance that any two photographers, anywhere, would do so is, I bet, pretty big

Not necessarily, but the the chance of any crazy coincidence happening and reaching HN homepage is quite big. Next time it might be two people with same name writing the exact same tweet independently. Or perhaps one guy winning the World Series of Poker two times in a row with the same winning hand.

When there's a million "kinds" of crazy coincidences, the chance of any one of them happening is much higher than chance of a specific one happening. This is kind of a selection bias, we only hear about the coincidences that happened.

I think that's an important insight because it also plays a large part in many conspiracy theories. Basically if you look hard enough for any kind of statistical oddity you'll always end up finding something somewhere. If you only cherry-pick these data points and ignore the billions of "true negative" correlations it's easy to reach the craziest of conclusions. It's the same idea behind "anecdotes vs. data".

But the coincidence that makes it to the top of HN is when the poker guy wins his third WS using the exact same hand. (At this point he played the hand entirely out of superstition at a negative EV but got insanely lucky. He will eventually lose all his winnings playing that hand again and again for the rest of his life. But they’ll name the hand after him, so maybe it will all have been worth it.)

I'm curious about your WSOP mention - did you single this one out because it (remarkably) did happen before? Or were you speculating it could happen again in the future?

Not aware of it happening before, just a random example.

Interesting! For reference, it did happen once before. In 1976 and 1977, Doyle Brunson won the WSOP with the same hand - 10-2 (a terrible hand), and it's now named after him.

The odds of the same person winning the WSOP now at all are significantly smaller as the fields have grown so much, never mind the compounding of winning it with the same hand twice :)

(To clarify, it was not the exact same hand - different suits in each case. But still pretty remarkable!)

Oh, I was only vaguely aware that he won twice in a row, so I included an additional condition cause I wanted something that didn't happen. But I guess that subconsciously I had the fact that it was the same hand in memory.

The birthday paradox arises because the probability that two candidates do not match is small compared to the number of candidates. In this case, the candidates are photos and a match in fact requires a match on multiple variables (e.g. angle, timing) that are effectively continuous. A match between 2 arbitrary photos must then have zero-ish probability and a non-match must have one-ish. So it still seems inestimably improbable that something like this would happen.

I'm not so sure. While there are multiple variables, chances are the number of landmarks in a given area that a professional photographer will consider likely to stand out as worthwhile in a storm is not all that great. While I'm not a professional photographer, I can think of maybe 3-4 places near me, for example.

And storms do not happen that often, even in places that have them "frequently", and they delimit the time, and even further by e.g. limitations such as whether the wind is too strong or the rain too heavy.

The number of locations they're likely to consider good spots to take the photo from for a given landmark may not be that great either. Both in terms of where you can actually see the landmark from, and in terms of other factors (e.g. in this case the article writer points out that both photographers had found places where they could protect themselves against some of the effects of the weather)

So that narrows locations and timeframe significantly.

Professional photographers are likely to take their time - the article writer mentions 40+ minutes of shots, and using bursts, further increasing the chance for an overlap within already relatively narrow time frames.

Additionally, external events that are the same for both (the waves) will give impulses to both with respect to when to shoot (though of course they might value different things, I'd argue people are more likely to shoot when something dramatic happens - e.g. if you have a dull day and suddenly something happens, you don't expect the pictures of that day to be evenly spaced afterwards).

I'm not saying we should expect it to happen all the time, but I also think it's easy to overestimate the number of possibilities because we've not tried to enumerate which ranges of values are actually likely.

There are probably well over 10 trillion photos taken. Less by professionals, but they are more likely to take the same photo.

Anyway, that low probability applies to every other photo. So, the first photo is compared to every other photo and by the end your talking ~50,000,000,000,000,000,000 comparisons. The odds would have to be mind boggling tiny for this not to happen all the time.

You're missing the other dimension to this: it's not that two photographers took pictures at the exact same time, I'm sure that happens frequently. It's that they took the exact same picture. There were definitely not 10 trillion photos take of this lighthouse in new england.

They don't have to be photos of this lighthouse. Two photos of Old faithful showing the same spray and cloud patterns could be mistaken for copy's of each other.

Another way of thinking about it, what are the odds that out of the ~1,000 photos taken of the same moment they are of the same subject? Now repeat that question 10 million times and the odds don't seem as low.

Especially if people are clustering around interesting happenings.

It's made more remarkable IMO that they were two _professional_ photographers though, and that it's not just two snaps that happen to have the same timestamp, they both chose that moment to feature from the burst they probably took around that moment, the hundreds of other moments in proximity, and the thousands (I suppose? I'm no photographer) they each took throughout the day.

It's made more likely that they (when there's first an overlap in their shooting) would select the same picture by virtue of getting roughly the same shots and their shots being likely to have many of the same qualities. Chances are they'll value many of the same qualities and so would at least exclude shots of many of the same moments for the same reasons.

That they're professional photographers might reduce the odds by virtue of there being fewer of them, but might increase the odds by virtue of them being more likely to be the kind of people to know of specific spots to go out of their way to take pictures from during a storm, and more likely to value the same qualities i their shots, as well as more likely to publicize their photos enough for one of them to find the other persons photo.

and even more likely if they both picked the shot where the wave crashed the highest

That fact makes it possible, but as he pointed out, they were taking photos at different rates of burst mode, and even then they happened to snap at the same millisecond. Usually each picture in burst mode of moving water is completely different. I think in that gas it makes sense that they would choose the same subject and the same photo since it was probably the biggest splash from that wave. As if they were choosing from the same set of photos, even though all their other photos had different moments.

I question the exact same millisecond part. There’s zero proof of that (and actually counter proof examining the photos). Same second, sure. Same millisecond, I think someone is reaching a bit much to make a story.

As I said in another comment, I'm pretty sure "same millisecond" is being used by the photographer in the sense of "same instant" or "same moment in time" not literally same millisecond based on a super-accurate time source. That information does not exist in the photo's EXIF data which is one-second resolution and typically derives from a manual time/date setting in the camera's menu.

I am not taking issue with the author of the post as I agree, that is likely the intent. But folks here seem to be parroting it as fact rather than taking the liberty you and I seemed to do.

That's true. I also think many of the readers of this site tend to take terms like "millisecond" literally and at face value :-)

I don't think the birthday paradox applies here. The birthday paradox requires a discrete set of pigeon holes, days of year, etc. If that set is infinite, then the countability [1] problem collapses.

While technically the world is discrete in space and time (planck length), for all intents and purposes it is infinite in practice.

[1] yes, there is countably infinite, but that doesn't work with the pigeon hole problem.

Isn't the birthday paradox just the dissonance between typical intuition and mathematical reality?

How does that not apply to this situation? The number of comparisons between photos is much much larger than the number of photos.

It might not apply in a way that is interesting mathematically, but I don't think that is what the other poster was getting at.

Reality may or may not be discrete, but what is a discrete value is the output from a digital camera, so in case of photographs your argument does not hold.

In other words, two photographs off by a planck length will generate the same set of pixels.

Sort of, but instead of 365 distinct birthdays you have many thousands of non-overlapping time buckets (the two different burst mode frame rate), and it also doesn't "wrap around" the way birthdays do.

Correct, but there are about eight orders of magnitude more milliseconds than days, and you need another two or so orders of magnitude because not everyone is a photographer who publishes their photos. Then again, the internet is a medium that reaches many more people, which is not true of the average birthday. So one would still expect this to happen only maybe every few years.

Well, but I am not sure that you would indeed require it to be the same millisecond. I mean I don't know how long the exposure was, but I guess its longer than a millisecond (just took a look at some of my own photos and they were at 4-5ms exposure in very bright sunlight, the blog image exposure is probably more like 10ms). The heading says that the pictures were taken in the same millisecond, but as far as I understand the post, they concluded it from the image, so I wonder what the precision is you can derive from a photo?

They said they compared EXIF metadata, so they should know when each of the shots were taken. I'm not a photographer and don't know what level of detail is recorded there, though.

The time precision that you can derive from the spray of the waves is a lot more precise that anything you will get out of the exif data - the wave will only have that exact captured spray pattern for a small fraction of a second, but the time synchronization on the two photographers cameras is almost certainly out by a larger amount of time than the wave looked that way.

Working with images from multiple photographers cameras who haven't gone out of their way to sync the time beforehand, I've usually had to assume about a 10s time skew. They do not have precise clocks and are not sybchronized often.

The time in the EXIF metadata is just based on the time/date stamp that's been set in the camera. I don't know about the newer Canon but I'm pretty sure the older model would just be something someone manually set.

Re-reading the article, I think saying the pics were shot at the "same millisecond" was just a colloquial expression to mean the look of the waves makes it look as if they were shot at the exact same time. They shared metadata but that seems to have been to share the other shooting parameters. I believe (and this would seem to confirm [1]) that EXIF timestamp data is only precise down to 1 second. added: and only as accurate as the photographer who set the date and time.

[1] https://www.media.mit.edu/pia/Research/deepview/exif.html

Both cameras (5DM4 and 60D) can be set via GPS using a Canon accessory, but I highly doubt that is the case (very few own that from what I have seen). Even then, the camera doesn't preserve millisecond data in the EXIF data.

Yeah, roughly the same 1/100th of a second seems more likely.

Shorter than a millisecond. One shot at 1/1000th, the other at 1/1600th.

Yes, you are right, didn't see that. So one is exactly 1ms and the other just 0.625ms.

[I felt like I was playing "Find 8 differences between these pictures" on the comics page]

I looked at the large images. Gendon's appears to have been shot slightly earlier based on two differences. 1. The crest of the background wave at the left is horizontal in Gendon's photo and turning down from photo left to right in Risman's. 2. The trough in front of the breaking wave has reached the front of the light house in Gendon's photo exposing a sunlit rock at the lower left of the low circular structure.

A rock broke wave is most photogenic at the moment of maximum spray extent. The water is at lowest velocity and the gestalt shape is briefly frozen...then gravity dominates and the moment collapses. The shape of the spray is the second most stable element in the scene. While it is the defining photographic moment, it is not clock correlated down at the millisecond level.

I looked at the two photos as a stereogram--focus through the plane instead of crossing your eyes.

If they were identical, there would be no 3d effect. My eyes can't figure out how to resolve the foreground waves, because the photographers were too far apart, but the spray wraps around the lighthouse as you would expect.

As a side note, it is possible to train yourself to stereogram your eyes at will (I've done it).

This makes "spot the difference" puzzles a triviality.

Which is, in itself a triviality, but an entertaining one.

I actually got a slight amount of use out of this recent with one of the Super Mario Odyssey hint arts: http://oyster.ignimgs.com/mediawiki/apis.ign.com/super-mario...

I also recently discovered you can make plain-text stereograms:

    O  O  O  O O   O O   O  O  O  O  O  O
I'm sure I'm not the first but I was still amused.

It helps to use registration marks to establish the base focal plane. Compare:

           <>                    <>
    O  O  O  O O   O O   O  O  O  O  O  O

           <>                   <>
    O  O  O  O O   O O   O  O  O  O  O  O

The carpet in my office frequently fools my eyes into the wrong focus. I have been tempted to use a marker to leave a secret message in it for my successor, but that seems like more work than my actual job.

I somehow assumed everyone could do that. Another item to put on the super-power list.

This is a great effect! The resulting image is quite stereoscopic (in an exaggerated way) and you can see the stone structure as clearly in front of the lighthouse as well

I once plugged my usb cable in on the first try. Goes to show you anything is possible!!

Edit: upon further inspection it turns out it was USB-C. Nevermind, all is right with the world :)

The real issue that usb cables are four-dimensional[1]. That's why applying three 180-degree rotations will return one to its original orientation.

1. https://www.smbc-comics.com/index.php?db=comics&id=2388#comi...

Something I learned a few weeks ago (after many years of using USB) is that usually cables have the USB logo or marking on the "right side" up. So if you don't know which one is the right side up, the one with the logo should win.

Might help some other lost souls here :)

This works until you need to plug something into the back of a computer with vertical ports.

Same with my monitor! I've found that what would be the natural axis towards you usually work, at least both on my TV, desktop computer (because of course you have the chassi on the right) and monitor.

or the port on your keyboard is upside-down. -_-

i know it's a joke, but the usb logo on the plug is always on top, so you can just orient it 'up' according to the underlying board (up for laptops, and facing left for desktops)

Yeah, but then you're just guessing at the orientation of the board, so it's still anyone's guess.

Apple cables have their logo and USB, if I recall correctly, and they always get me confused.

Ok I'll open up my computer case to see which way the board is mounted.

He already told you, left is up.

The side of your case that has the motherboard's backplate (where you plug everything in) is the bottom. On the vast majority of towers, the plate is on the right side, meaning left is up.

EDIT: right/left when looking at the front of the case.

A few months back I gave a Trader Joe's blueberry muffin to my son.


As usual I cut it in half straight down the middle. As usual I paid no attention to cutting it. I was just about to hand it to him when I noticed something strange, so I quickly took a photo...


The chances of the cut aligning the way it did, the blueberries lining up the way they did, the cut cutting the blueberries exactly in half, the blueberries ending up in this exact formation, me buying this specific muffin, the rotation of the muffin when I cut it....

Well, it just seems impossibly unlikely for something like this to have happened, yet it did!

The fact that the blueberries sunk to the bottom could indicate that there was too much liquid in the mixture

I would love to see these in a stereoscopic viewer. If they really were taken that close together in time, and given the huge binocular separation, there should be a hell of a 3-D effect.

Check out the comments at the bottom of the article -- "trialex" put together a "wiggle gif" version (https://uploads.disquscdn.com/images/42ab07151119e1a3d5a43fa...) and "Michael Wise" posted a cross-eyed version (https://uploads.disquscdn.com/images/2903120ac9e726088a33b8d...).

Wow! They should make this into an actual one of those stereographic pictures!

If you squint your eyes enough you can make them overlap and sure enough you get a perfect piece of 3D. The water at the front is a mess but the lighthouse and the spray have real depth.

It's possible to judgde the relative positions of the photographers by eye based on some of the waves directly under the lighthouse. In Eric's picture there are some distinct crests immediately below the lighthouse door. In Ron's picture the exact same crests are on a diagonal line from the door toward the lower left corner of the frame. Tracing this imaginary line "out of the picture" would lead us to Eric's position, which means that Eric is to the left of Ron.

Literally the same millisecond (according to timestamps), or ‘only’ the same tenth of a second or so (as demonstrated by the pictures being near identical)? Those would both be unlikely and remarkable events, but one is 100 times more unlikely than the other :)

Timestamps are not useful for this since the cameras clocks are likely off by more than a millisecond.

I think a millisecond is too strong of a claim, but it's almost certainly much less than 1/10th of a second. (a simple though experiment that you could turn into a real experiment if you have a camera: If you take a 1/10th second exposure of something like this the magnitude of the motion blur will be much greater than the differences between the wave shapes on the two cameras).

So if two people are shooting in burst mode, and both have an overlap in their shooting burst of say 2 seconds with 5 images per second. Then the chances is already (2 * 5)/1000 to land a picture in the same millisecond.

You'd expect in 100 burst of pictures taken like this for one to be taken at the same millisecond.

It's not that unlikely. What's more unlikely is that they selected the same shot and found out about it. This probably happens multiple times every day, just by virtue of the billions of people in the world taking a photo every day.

In the vimeo video he shows the other burst shots in Lightroom. A tenth of a second before/after is noticeably different.

The time frame in question doesn't seem that big. There were probably not that much large breakers and the they both chose the peak of one with the best conditions. So maybe a 1:100 to 1:10.000 chance. I'm more amazed, that they went down the whole photoshop route before comparing angles. If someone had that kind of skill in retouching, he wouldn't need to copy photos to make a living.

The foreground wave is definitely from a noticably different angle, but still the same scene, even the white caps in the far background look very different. You don't need a high res image for that, only, when cropped to the lighthouse only.

No more than 1/100s apart.

My guess is that the water doesn't move much faster than 10 m/s which translates to 1 cm/ms. You certainly can't make out 1 cm differences in the images, so the "same millisecond" claim is definitely exaggerated. From a quick look, the time difference could even be more than 10 ms, but not by much.

When I first joined my local photographer's club, one of the masters there told me that I need to accept that all the photos I will take will have been probably already shot by someone else. Obviously not that realistic, but articles like this sure make it sound more plausible.

> all the photos I will take will have been probably already shot by someone else

> Obviously not that realistic

Depends on how literally you want to take it. Lighthouses have definitely been photographed before. Photos depicting the man vs wild nature archetype too.

Totally cool, but not unlikely. With the sheer volume of high-end cameras and photographers using burst mode, this will certainly happen time and time again. It’s likely that this happens several times most days.

Some simple math: one camera was taking a photo every 143 milliseconds (roughly) and the other every 196 milliseconds (roughly). If both sit in burst mode continuously, I would expect these cameras to share the same millisecond (meaning each photograph took place within 1 millisecond of the other) every 28,000 milliseconds (roughly) or every 28 seconds.

I’d also argue that the details of this ‘unplanned’ event increased the likelihood that two photographers would select the same photo out of a series of bursts - didn’t the author say only about 3 images came out nice? Well, I imagine the other photographer had the same experience.

The amazing thing here is not that they took a photo of the same thing at the same time, but that this fact was discovered.

With the vast data capture exercise that is the internet, coincidences and patterns can be identified in near real time. Making sense of it all, however, is not so quick :-)

Cool idea for a service like Flickr (or at least Flickr in its prime, which is not now) to exploit -- given EXIF data and a database of photos, one could find all the photos taken in the same location at the exact time. While almost no cameras embed GPS information, I bet there are ways to infer the location in many cases.

This was in fact the business of the infamous Color startup[0]. For those not familiar, they raised a ridiculous amount of money, then shut down and returned most of it to the investors. My favorite memory of Color was when they became a landmark when they bought a massive office in downtown Palo Alto, got hit with zoning restrictions which forced them to use the ground floor for retail or leave it empty (they left it empty).

[0] https://en.m.wikipedia.org/wiki/Color_Labs

I had a similar project prior to Color coming out with it. No one seems to care about proximity photos for events.

5d's image looks remarkably better in terms of colour depth and details.. wondering whether it's due to the sensor size (full frame vs aps-c) or some other factor?

As is shared in the article, the largest contributing factor is likely how Lightroom was used during post-processing.

Although there are differences in post-processing, you can see significant differences in quality in the zoomed-in crop:


This is not surprising considering we're comparing a 60D that was released in Aug 2010 and a 5D4 released 6 years later.

That's true, but Risman is clearly very liberal with photoshopping ("moon-stitching" liberal), and it seems to me that that's the largest factor.

The turquoise tone in the waves has been overlayed (it's fake, in other words), and I bet other areas of the photo has been very heavily modified in an artificial way.

I would be curious though to read a professional analysis, since this is a very interesting (and I think rare) case of how a photo looks before and after fabric... I mean, after "art has been applied". /s

(Also, I wonder if Risman used a polarizing filter, while Gendron didn't, as it generally contributes to this type of difference (deeper blue tones, and increased resolution due to dehazing)).

A photographer makes a lot of decisions before collecting the data (ie. shooting) and a lot more in post-processing.

Framing and timing the shot are some of the most important ones, and here they were almost exactly the same. But even at the time of shooting, given the same equipment, you'd have the choice of aperture, shutter speed, sensitivity (ISO). Also things like whether your lens is in the sun or the shade may affect the result tremendously. If you made these choices well, you have unspoiled data with a good dynamic range, and that allows all kinds of post-processing. And of course post-processing is an art in itself.

What I'm trying to say is, photography is more about skill than equipment. In the given situation there was a lot of light so even a relatively bad camera equipment would have sufficed.

The histogram could just be stretched differently for both photos. By changing the gain and offset of the picture, you could possibly get more closely matched photos.

I will edit this to reply properly later but from the pic it looks like the main difference is the lens

Are you just looking at the low resolution images in the article? If so, I think most of it can be attributed to post-processing. At that resolution the sensor size isn't going to make a big difference.

But I wonder why I cant get the same "look" (despite post-processing for ever) similar to the wallpapers of yesteryear which were mostly 720p :)

http://www.dictionaryofobscuresorrows.com/post/102182393150/... is a lovely philosophical rumination on this kind of thing.

Reminds me of the time when my sister and I took pictures with very similar composition of the sky - and you can see the same clouds in each photo.


I love things like this.

Sorry but this is not coincidental or crazy in the slightest!

You both snapped a picture of the sky minutes apart on your way home because the sky looked nice. Okay, so what? There is nothing unusual about that. The photos are different. Clouds in different positions, different focal length... I don't see "connected minds". I see "hey, cool sky" [whips out smartphone, snaps photo].

Compared to the source article, it's relatively mundane. I don't claim otherwise.

I'm not a photographer. I don't claim to be. Maybe this event I experienced seems much more common for someone who describes themself with 'dev/design/photo/animation', but for me it seemed pretty unlikely. I don't take photos often (The last photo I took in my gallery of my smartphone is dated December 2017).

The crazy thing for me and my experience was how close in time the two images were (considering neither of us are photographers/regularly take photographs), and how you can match the patterns in the sky to estimate my position relative to hers. Something like this had never happened to me before.

One man's junk is another's treasure and all. :)

Sure, okay... all good and no offense intended, but... .

> I don't claim otherwise

You kind of did by making a web page called 'connected minds', saying "something crazy happened today", describing the photos as same clouds and "near identical", then sharing the link.

Be prepared for feedback when you do that! This isn't about me asserting myself as photographer in the room. We all carry cameras.

It sounds like you both live at same location, you were on way home, snapped photo of sky at similar times, as probably others in your neighborhood did. I'm not calling that "junk", I'm just not sure the claims you make equal the event! But let's move on.. all the best, take more photos! I checked out your homepage... Wow, now that is crazy! :)

Alternate title: two photographers learn about the birthday paradox...

Not really. The birthday paradox is a paradox because it describes a circumstance that seems unlikely but actually is not. In this case it both seems unlikely and IS unlikely. If it were not unlikely we would see it happen more often.

Like I posted somewhere else here, it likely happens hundreds of times a day (going by millisecond granularity and # of photos being taken per day in close vicinity in the world). That people afterwards see each others photos and find out about it is rather unlikely.

It probably happens most days in the Louvre at the Mona Lisa. Although she doesn't move very much.

So it's a publishing coincidence rather than a photographic one.

It's unlikely that it would happen for any given shot, but it is very unlikely that it would never happen across all shots taken, which is the crux of the birthday paradox.

Exactly. This guy statistics.

We are sorry about that glitch in the matrix.

I'm glad this isn't a horror story about one person suing another, thinking they had stolen their shot. Happenstance fun-ness is better!

that is absolutely incredible! Very happy they actually figured out its not a copy and different lightroom effects. It did seem slightly different positions in the original compressed images.

Two professional photographers having independently selected the exact same frame from two different bursts they captured with their cameras is an interesting instance, illustrating the pro-AI argument in photography and possibly adjacent creative domains.

Grossly simplified, two humans went through dozens or hundreds of shots with identical internal “algorithm” and did the same work twice. This shows that the algorithm can be “abstracted away”, and the work can be done for them by the machine.

I can roughly see the counter-argument to be made, considering true creative self-expression and art losing value as its hardest aspect becomes optional (“natural selection” of produced work via artist’s taste)—but it’s hard to argue, in the light of this example, that professionals would find such a tool indispensable.

Sorry but I do not agree at all. First, the fact that they chose the same photo might not necessarily mean that photo is the "optimal choice" according to some algorithm: it can perfectly be a coincidence. I find it even more improbable that a tool that selects "the best photo of a bunch" is useful for a significant portion of the photographers (as in "it gives results according to their tastes") unless it takes into account only basic measures and they can use it in specific instances (e.g. find the photo with the best light exposure).

> First, the fact that they chose the same photo might not necessarily mean that photo is the "optimal choice" according to some algorithm: it can perfectly be a coincidence.

Well, obviously it does mean that; the photo was the optimal choice according to the two algorithms used by those photographers to choose their picture.

Does that mean it would also be selected by another equally good or superior algorithm? No. But it does necessarily mean that the photo is the optimal choice according to two algorithms.

The algorithm could simply be "randomly select an image from all the burst frames."

True, but the image in question would trivially be optimal according to that algorithm, as it considers all images equal. If all images are equal, there is no image better than this image.

A simple explanation for the image selection match might be that the wave is at its highest point in the chosen image.

At this lighthouse location, photographers are looking for that shot.. they wait for the wave, then shoot. There might only be a handful of images in the burst that qualify - perhaps less than 10, so the coincidence is not that amazing. It's cool, but not "scary freaky" coincidental.

Now if they were using a single shot camera, that would be more amazing.

These aren't the exact same frame at all. They are photoes of the same thing, that's certainly true, but the photoes are quite different. Risman's photo is way more dramatic and moving with all that contrast, bright, defined colours, and dark shadows. Gendron's instead looks quite composed, with pastel colours and less distinguishing details, and has more of a quiet grandeur to it. They'd hardly pick the same photo from their bursts if it was not for the big wave that struck the lighthouse. Artistic expression includes the selection of the scene, but also more. It's in the way the cameras were set up, the photoes were post-processed, the way accents were decided, and how the photoes are perceived now that we are seeing them.

That there is one instance of two photographers choosing the same "best photo" does not show anything general. And even if there were some universal consensus for "best photos", whether machines can do it is an entirely different question.

I wonder why they had to look at the iron bars to find the difference in position. If you look at the waves in the foreground the difference is very obvious.

Nevertheless, quite cool incident. Not just that they took a very similar photo, but also that they found out that they did.

The author addresses the displacement of the foreground waves: "I know those things are easily moved using the clone stamp in Photoshop", and he demonstrates it in the accompanying video.

Yeah, but that is related to the photo being a rip off. Manipulating the bars in the tower would be even simpler.

One thing I do for a hobby in addition to my usual interest in photography is enhance images in the public domain (e.g. combine the color separations of Prokudin-Gorskii's images into color images, merge multiple images to reduce noise or create a panoramic image, or find stereo pairs of images a lay them out for cross-eye viewing -- so in the same spirit, without as much work as those who colorize historic images).

With that background, it's apparent there should be enough parallax, even given the long distance to the subject due to the claimed distance between photographers to create a stereo pair using the two images (some photographers make hyper-stereo images of mountains and clouds). If one image were derived from the other, it should be obvious -- the differences between the images would only be skin deep, e.g. the waves in the foreground, the different position of the bars at the top of the tower, but the entire body of the wave would be identical.

Overlaying them and subtracting the difference, it can be seen that there are slight variations across the entire image, and when viewed as a stereo pair, there is an obvious stereo effect, the platform in front of the tower appears in space in front, the wave appears to wrap around the tower.

What we're left with is the story that these two photographers didn't coordinate their images. I see no reason to disbelieve this. Like was stated elsewhere in this thread, the title is incorrect and the images weren't taken the same millisecond, so that makes the story less remarkable.

> and ultimately we both selected the same photo from that day to promote.

That’s the funnest thing about this story imo. These kinds of photographers shoots hundreds or thousands of photos in half an hour. It’s wild they were both struck by one particular exposure.

Things move a lot in a millisecond, although it's certainly easier to see that in small-scale images rather than this lighthouse one.


This is a picture that I took in 2009; you can see the ball coming off Ken Griffey's bat after breaking it.

A major league fastball comes off the bat at 100+ miles per hour (45 m / s). The shutter speed was 1/640s (about 1.5 msec). The ball is about 7.26 cm in diameter.

Nice example. To make your point clearer: that motion blur is how much the ball moved in just 1.5ms

Exactly, thanks for clarifying.

And also why I was shooting with single shots to try to time the ball close to the bat. Given a camera that took about 5 frames per second (200msec between frames), the ball would move about 29 feet (8.8m) in between frames.

The breaking bat was a nice surprise.

In 2006 I shot a different kind of coincidence that made me wonder about the uniqueness of our actions: 10 minutes apart, two unknown men walking on a street, both with jeans, black jackets, white hoodie/cap, black shoes, the same leg in front and with their feet on the same spots on the ground: https://hamoid.com/post/2006-07-dimensions-of-the-city/ (photos #7 and #8)

Off topic, but I am trying to get my head around the photo #14, it's almost like an optical illusion but not quite! Looks almost like a photo that has been mirrored vertically but since the men are in different position, the halves must be different photos (one mirrored). How did you get the hoses line up at the middle position? I'd like to hear how this photo was created!

I find it fascinating that the waves look so different when photographed from a slightly different position. Maybe the waves also change faster than the spray around the lighthouse?

The closer you are to something, the more quickly it appears to "move" when you shift your viewing position. The waves are much closer than the lighthouse so as you move left or right, their perceived position moves more quickly than the lighthouse. I guess the technical term is parallax?

Yes, when looking more thoroughly I could recognize the waves in the two images, indeed moved quite a bit.

While the coincidence is real ... why couldn't these shots have been 1 millisecond off from one another? The shutter times are short enough for it...

I know it's nit-picking, but why make that the title?

Otherwise, it's also definitely worth noting that these were shot with burst mode, so that the chance of this happening is ~.7% --- definitely very unlikely, but still much more likely than most rare events you read about in the news.

the same sub second... splash's movement frozen in time is not at the ms level precision....

Also the scenario described here is not that rare.. Once you have two photogs there that day, your chances of getting the same shot is already pertty good. The two photographers were essentially firing off continuous shots when they anticipate a wave hitting... Everyone was focused on the lighthouse...

This would make an interesting copyright case.

I found some discussion of copyright infringement by imitation here: https://dc.law.utah.edu/cgi/viewcontent.cgi?article=1019&con.... [0] In general it seems to be fine to photograph the same object as an earlier copyrighted work, as long as "original aspects" are not copied such as lighting or placement of the subject. The lighting is different here, though the placement barely differs. There's also not a clear "first" since the photographs were taken almost simultaneously. I think at the end of the day, a judge would chock up any alleged infringement as de minimis. [1]

This also brings to mind the image of paparazzi or sports photographers all in a narrow press area rapidly shooting off pictures. I don't think any of them have had trouble selling their photographs to agencies despite being in the same location and capturing the same subject simultaneously.

[0]: Kogan, Terry S., "How Photographs Infringe" (2017). Utah Law Faculty Scholarship. 20. https://dc.law.utah.edu/scholarship/20

[1]: https://en.wikipedia.org/wiki/De_minimis#Copyright

Except that the two pictures are not exactly the same. Once you start looking for differences, you find small ones. For example, the article points out the two differences in the lighthouse. In the foreground of Gendman's picture is a whitecap that is on the left in Risman's picture.

Statistically, this is actually really not that surprising.

Both photographers take multiple shots with a short shutter, usually from the same places, and usually trying to pick the same events. So the only coincidence is basically having two photographers be at the same place and time.

With probably hundreds of photographers at pretty crowded/famous spots (say sports, famous buildings, or nature places) and using long shutter speeds, should not these improbable coincidences be not so improbable?

It's a picture of waves crashing at high shutter speeds to be able to sharply capture the scene. having the same picture of a person (slow moving) or a lightning (slow shutter speeds) is much easier.

If two photographers shoot the same millisecond in time, who owns the copyright?

In this example, there were discernible differences, but what if the differences were below our level (or care) to discern them?

No one would likely have copyright over the actual event (or if they did, it would be a separate discussion). Each photographer could have copyright over their image they took.

Even though their images are identical?

I'm reminded of that quote by Gordon Letwin talking about software bugs and rare events - "in our business one in a million is next Tuesday"

This was the next Tuesday of the photography world.

Maybe somebody could use these photos to legally destroy concepts of creative input / originality in non staged photography and remove copyright protection from such works.

Wasn't he shooting continuously for 45 minutes? That's 3% of a day. Wouldn't he have a shot of the same millisecond of any photos taken during that time?

He only chose one to post online. So it's much less likely than that.

There are 1000 ms per second, the camera he used takes 7 frames per second.

With the described margin of error, that would be more than enough for "identical" photos.

I see a lot of differences in the waves, so I'm doubting the "exact millisecond" statement. Perhaps within a few tens of milliseconds.

I think that difference is due to the different photographer view points. Both observers center on the lighthouse but from different standpoints. Everything in front of or behind the lighthouse will look different, even if they caught the exact same nanosecond.

I don't know what come to your mind after reading that article, but mine was: Oh man! Canon 5D Mark IV is truly far better than 60D.

Shopping cart added.

That is one hell of an impulse buy. Would you care to hear my sob story and startup idea?

Amazing how different cameras capture the same picture from almost the same angle at the exact same time in totally different color tones

I believe its's more due to post-processing in Lightroom.

And Ron is the better photographer. The other photo is a little bit over exposed.

This assumes that both photos were not edited.

Ron already admitted his was edited with adobe lightroom.

this is really not all that hard to do ... all you need are 2 photographers equipped with cameras that can to better than 12 frames per second (EOS 1Dx for example) and fire away simultaneously at the same subject ... then go through the bursted images and find the files that match ...

This is one of a rare coincidence.

Law of large numbers.

It's why we exist at all.

That's very interesting. Try to think of what the probability of that happening is.

" ... the lighthouse had slightly different spacing between the vertical bars compared to my image. This would indicate that the other photographer was likely standing just a little bit left of where I was standing."

I could already tell that from the shift of the white caps on the waves midway in the ocean

This would be the perfect occasion to make a stereoscopic image.

You can get a nice magic eye effect from the photos, too.

This made me so happy! I have a glee from ear to ear!

Copyright requires original artistic expression. If two people do the exact same thing, that is in doubt.

Acshually...this happens thousands of times every day, due to a phenomenon called collisions.


that was stunning!


The waves look very different, especially on the left side

This happens a lot. You could probably find 20 photographers in my area who capture frames with the same timestamp during a sunset by a lighthouse.

If you look at the waves in the water you can tell they are different.

Same millisecond? Prove it... I would buy same 10ms. If two cameras with frame rates of about 8frames/sec were shooting at random, the probability that they are in the same millisecond is very low, like 1.5% or so. If they were in the same 10ms interval... more like 14.5%! Actually not that low, and the apparent difference in the waves might not actually be significant in 10ms (supposing the water was at it's maximum height 10ms^2*9.8m/s2=>less than a mm of movement!). Suppose that within a cm the photographs look the same, then this implies a time interval (at max water height) of 31ms. Over 31ms given the snapshot intervals there is about 38% chance of the photos being of the same 'moment'.

The skeptic in me thinks this was planned. Yellow submarining given that the author is selling something

would be insane if it were a marketing stunt too! Taking the same picture of the same moment of a huge unplanned wave would be a feat worth of the marketing purpose.

Well you could trigger pictures from the same clock and wait until something interesting happened...

the article says that at least ron was shooting for 45 minutes. Which is an average time, but if you consider how many photos a modern camera takes per second...

its technically possible to plan, but just as likely to happen on accident. And its definitely a wonderful example why the idea of intellectual property for photographs is a flawed concept.

But its not an easy topic and photographers still need to earn their living. That means some protection from publishers that just take their shots without paying.

Suggesting something on the internet is fake is a fool's errand. Anybody can do it about anything so it's worthless. What else might be fake? The story that it happened? Maybe he just took one photo and photoshopped it! Maybe it's not really a photographer at all. Maybe you live in the Matrix. This kind of reasoning goes down a black hole to nowhere.

You have to maintain a basic level of trust in the source of information if you're going to have any interesting thoughts about it. Finding actual evidence of fakery would be worthwhile, or checking some features and reporting how you found none would be too. But there's no value suggesting it just because you feel cynical.

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