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Create Your Own Bullet Time Camera Rig With Raspberry Pi

timothy posted about 10 months ago | from the price-elasticity-of-frippery dept.

Input Devices 88

sfcrazy writes "A team of extremely creative people have created a really inexpensive bullet time set-up using Raspberry Pis — and the whole set-up costs less than a professional DSLR camera. The rig looks more like the LHC at CERN using nearly half a kilometre of network cables, 48 Raspberry Pis fitted with cameras and PiFace Control. The rig worked perfectly — in terms of doing what a bullet time set-up should do. Raspberry Pis achieved the Hollywood's 'frozen time' effect at a much lesser cost."

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Affect/effect (0)

Anonymous Coward | about 10 months ago | (#45624805)

Submitter either meant 'effect' or is being a little sarcastic about the prevalence of bullet time.

Re:Affect/effect (3, Funny)

Anonymous Coward | about 10 months ago | (#45624847)

Submitter either meant 'effect' or is being a little sarcastic about the prevalence of bullet time.

Nah, I do special affects all the time.
Especially around people I don't like.

Re:Affect/effect (0)

Anonymous Coward | about 10 months ago | (#45625271)

+1 awesome

Re:Affect/effect (-1)

Anonymous Coward | about 10 months ago | (#45625883)

Who are the assbusters? Between the buttcheeks more than 30 years of special effects experience.

Re:Affect/effect (2)

gl4ss (559668) | about 10 months ago | (#45625061)

submitter was in awe about raspberry pi and the eeeextreme creativity.

now, 40 bucks(tax, power source, sd card) or so for a remote trigger is fucking expensive.

I thought they were using one and some micros from the tagline, but if you need 40.. if you're using the pi as an atmel/pic replacement something went wrong.

Re:Affect/effect (4, Insightful)

foobar bazbot (3352433) | about 10 months ago | (#45625219)

I don't think you get it -- each station has a ~$40 RPi-B, a ~$30 5MPx camera module, and a ~$30 LCD+buttons board (which AFAICT serves no actual purpose in this project, but is the product being sold by the people who put this project together to promote that product, so it kinda has to be in there).

You'd use an AVR/PIC at each station to control a point-and-shoot digital camera -- and a $40 RPi would be insane in that role. In this case, they're using the RPi not to control a standalone camera, but to be the mainboard of a digital camera. Depending on the smarts present in that camera module, and particularly on how slow a data rate it's capable of speaking, an AVR/PIC might be able to handle this, but it would be some heavy lifting. From that perspective, it almost makes sense -- if only a CHDK-capable P&S weren't basically the same price and a whole lot more featureful.

Re:Affect/effect (3, Informative)

gl4ss (559668) | about 10 months ago | (#45625247)

..and you wouldn't compare the picture of a p&s with the camera module either.

I don't think the pi camera modules do much processing on chip though? so I guess the thing to compare here would be comparing it to buying 48 eight mobile phones at 70 bucks(j2me or the cheapest possible pos androids you can find) or so and sw.

I'm just irritated by the headline. the headline implies a single raspberry which for controlling all the cameras would be kinda neat BUT if you buy 48 raspberry pi's with cameras then going to the bullet time recording is rather trivial(you would still need some creativity to use it to create something creative of course).

also, better uses for 48 cameras in an installation: 3d scanning.

Re:Affect/effect (1)

K. S. Kyosuke (729550) | about 10 months ago | (#45626813)

also, better uses for 48 cameras in an installation: 3d scanning.

Or, just use a single camera and a turntable.

Re:Affect/effect (0)

Anonymous Coward | about 10 months ago | (#45628685)

Or, just use a single camera and a turntable.

unless your turntable can turn at really high speed while marking full stops during the exposure, that would be much less practical since it would require the subject not to move. That's okay for scanning a teapot, not so for a living being or other moving targets

Re:Affect/effect (0)

Anonymous Coward | about 10 months ago | (#45626665)

don't apologize, that was awesome!

I was thinking usb webcams on hubs make one pi run however many it can handle before it craps out, in this case arbitrarily lets say 8 cams per pi. if a pi costs 40 bucks, and a decent 4 port usb hub costs 20 bucks that's a pi port density of 8:1 so you should be able to do this with 6 pis running 8 usb cams each to handle the cameras and one other console pi. And... NO CRIMP TIME

assuming the pi can do more than one camera at a time. I'd like to know why it can't.

Re: Affect/effect (0)

Anonymous Coward | about 10 months ago | (#45628775)

USB on these things is horribly broken and can't be fixed.

Re: Affect/effect (0)

Anonymous Coward | about 10 months ago | (#45633581)

No it's not.

Ok? (-1)

Anonymous Coward | about 10 months ago | (#45624809)

Ok.

sort of (1)

phantomfive (622387) | about 10 months ago | (#45624859)

Raspberry Pis achieved the Hollywood's 'frozen time' effect at a much lesser cost."

Really, judging from the movie in the link, the lesser cost was rather obvious in the quality of the product. Still cool, though.

Re:sort of (0)

Anonymous Coward | about 10 months ago | (#45624883)

They didn't even shot something showing the effect. The whole point is to freeze something moving. Shooting two kids sitting still is kind of pointless. You can do that using one camera moving in a circle for a lower cost.

Re:sort of (1)

umdesch4 (3036737) | about 10 months ago | (#45624923)

I have to admit, seeing their setup, the first thing I thought they would do is make somebody jump, and take the shot while they're at the apex of the jump.

Re:sort of (1)

smitty_one_each (243267) | about 10 months ago | (#45625845)

Just shoot some HD, and pull out our Vadering shot as a still.

Re:sort of (1)

Java Pimp (98454) | about 10 months ago | (#45641685)

They would have had to set the rig on bar stools instead of chairs and I don't think their budget would cover that.

Re:sort of (0)

Anonymous Coward | about 10 months ago | (#45624895)

I prefer the Blues Brothers Mall Chase... Lego Style!

http://www.youtube.com/watch?v=bJ_uqlNgSU8

Re:sort of (0)

Anonymous Coward | about 10 months ago | (#45624901)

I couldn't really see if it was bullet time, I mean if you look the backstage video of bullet time in M.A.T.R.I.X. the action is actually 1-2 seconds and they stretch that with bullet time. In this one people except the lady are staying still. They could accomplice the same effect by mounting one camera on a mini train running on rails in a circle.

Re:sort of (5, Funny)

Anonymous Coward | about 10 months ago | (#45625003)

The "really inexpensive" part was what I thought was humourous. "costs less than a professional DSLR camera". Math is fun!

So the "best" DSLR right now according to reviews is the CanonEOS-1D X which can be had for ~$5500. Divide that by 48 because that's how many pi complete devices they used and we get $114.58. The Pi that they used was the $35 unit because they needed Ethernet. They also had a $30 camera and a $33 PiFace display on each. We're up to $98... oh wait, they used preloaded SD cards at $13 a pop, and we're up to $111 with no power supply. Fine, lets say that with bulk prices we get PS from the goddamn Loch Ness Monster for three fiddy a piece. Bam, we've hit or target. Or at least we would if we didn't have to factor in networking components, a custom "laser cut" frame, or 0.5km of cable and a days worth of time to crimp ninety six RJ45 plugs.

The TL:DR point is to stop giving us meaningless indicators of how much some shit costs. Just tell us a number. Did you know that this project supposedly costs less than the average trade in value of a 2005 Honda Accord? ($5775 [nadaguides.com] ) It costs sufficiently less than giving birth to a child ($8802 [parents.com] ) It even is less than the cost of eating a donut a day for thirty years? ($5962.50 @ $0.50 ea plus 6% sales tax) and that doesn't even factor in the added costs of type 2 diabetes!

So just tell us how much it costs. Everything else is just wasting our time. My apologies if you actually read through my entire post.

Re:sort of (0)

Anonymous Coward | about 10 months ago | (#45625217)

I'm just amazed no one has mentioned that they'll 3D print this whole setup.

Re:sort of (0)

Anonymous Coward | about 10 months ago | (#45625263)

They're only going to 3D print the Raspberry Pis. The rest is all "vitamins."

Re:sort of (0)

Anonymous Coward | about 10 months ago | (#45625479)

erm -- to do it with professional DSLR you need 48 DSLRs so that's 48*$5500 which is a factor of 48x greater!

You could do it with dslrs for this money (0)

dutchwhizzman (817898) | about 10 months ago | (#45625763)

If you're handy enough to set all this up, you could buy second hand DSLRs like the Nikon D70 or the D70s with a small problem like soldering of the card slot gone bad. Fix those and you'd be able to use DSLRs with a much better sensor than the crappy picam. Many a wedding was shot with these cameras, including sometimes usage of the kit lens.

Yes, I did factor in the cost of the kit lens, which the guy I'm commenting on didn't. If you're going to talk about the 1D-X you should add in the roughly $1500 for the lens too. Plenty of money to get the control stuff and second hand kit lenses for my D70 rig sorted out.

The fun bit here is that they did a bullet time setup with the RPI using Ethernet and home brew software. Yes, it'd cost less to do it this way than if they would use professional grade cameras, or even amateur stuff, but the image quality isn't better than the average web cam or front cell phone camera. It's an exorcize in setting this sort of thing up, not an attempt to get it done on the cheap.

Re:You could do it with dslrs for this money (1)

Desler (1608317) | about 10 months ago | (#45625957)

It's an exorcize

Someone was possessed by demons?

Re:sort of (0)

Anonymous Coward | about 10 months ago | (#45627407)

Mmmm, donuts.

Re:sort of (1)

Bucc5062 (856482) | about 10 months ago | (#45627493)

I, for one, enjoyed it

Re: sort of (0)

Anonymous Coward | about 10 months ago | (#45631545)

But you'd need 48 DSLRs. That's approx over 1/4 million bucks! Nice rant though. Kudos. :-)

Re: sort of (0)

Anonymous Coward | about 10 months ago | (#45633733)

But that's not the comparison made in the summary.

and the whole set-up costs less than a professional DSLR camera.

Need the LHC (3, Informative)

Roger W Moore (538166) | about 10 months ago | (#45625225)

Well for a real frozen time effect you need the LHC - time passes over 14,000 times slower for the protons in it than it does for us. Although it is a little bit less interesting on film given that the protons don;t really do much!

While I agree that the device is really interesting comparing it to the LHC is like comparing a pea shooter to a nuclear missile. Our "cameras" are 14 storeys tall, take 25 million pictures per second, have single cables that are over 500m long and took decades of work by thousands of people to design and build. The feeling you get when something that big finally works and, even better, discovers some new, fundamental physics is a little bit more intense.

Re:Need the LHC (1)

ultranova (717540) | about 10 months ago | (#45629203)

Well for a real frozen time effect you need the LHC - time passes over 14,000 times slower for the protons in it than it does for us. Although it is a little bit less interesting on film given that the protons don;t really do much!

Which reminds us: where are all the "LHC creates a quantum magic black hole and a hundred Arnold Schwarzeneggers from alternative realities must band together to terminate it" -themed disaster movies? Mayan apocalypse/calendar rollover has been used up, but the LHC is busily recreating Big Bang. You'd even have a ready-made excuse for any plot holes: "The LHC is distorting the time-space continuum! It's causing ripple effects!".

Just think about it: Conan the Barbarian, T-800 and the ex-governor of California all teaming together to fight an evil black hole!

Re:Need the LHC (1)

ediron2 (246908) | about 10 months ago | (#45630863)

I was going to point out to Roger W Moore that he missed the part where all OP said was 'looks like LHC', nothing more. Maybe a jab about overreacting.

But then I realized that I'm in a disturbingly tiny minority of the civilized world that geeks out at his 2nd paragraph and that his defensiveness is 'cuz he probably struggles to get 9/10ths of people he meets to understand why LHC and Big Science are a BFD.

Keep preaching the technological and engineering awesomeness, Roger. And kudos to everyone involved.

One camera w/ ceiling fan (1)

Anonymous Coward | about 10 months ago | (#45624879)

I thought the quality of this one was better - and it's got to be cheaper and more reliable:

http://jeremiahwarren.com/blog/2013/06/30/how-to-create-a-diy-matrix-bullet-timetime-slice-rig-using-a-ceiling-fan-and-a-gopro/

But the Raspberry Pi 3D body scanner with many Pi's was cool:

http://www.raspberrypi.org/archives/5232

Or you could...... (0)

Anonymous Coward | about 10 months ago | (#45624953)

hold really still, have a bullet on a string, move the camera around it and you're done, and maybe still be culturally relevant since you weren't waiting 13 years for this.

costs less than a professional DSLR camera? (4, Informative)

csumpi (2258986) | about 10 months ago | (#45624969)

48 rpis = 48 * $35 = $1680
48 cameras = 48 * $30 = $1440
48 piface = 48 * $34 = $1632
48 2gb sd cards = 48 * $8 = $384
48 5V PSU = $48 * 3 = $144

Up to here, it's $5280. Not including:

about half a kilometre of network cable
2 x 24 port switches
1 wireless router
custom laser cut frame
shipping

So let's say $6k. You can buy a nice professional DSLR for much much cheaper than that.

Re:costs less than a professional DSLR camera? (3, Funny)

mbstone (457308) | about 10 months ago | (#45625021)

No, no, no. Not $5280. He said "half a kilometre" which is $1640.

Re:costs less than a professional DSLR camera? (1)

Anonymous Coward | about 10 months ago | (#45625035)

You might buy a NICE DSLR for less, but that's about right for a PROFESSIONAL DSLR. That's why I have a NICE one.

Re:costs less than a professional DSLR camera? (1, Informative)

blackraven14250 (902843) | about 10 months ago | (#45625183)

Canon sells the EOS 60D under their professional section, for $900. The second highest, the EOS 5D Mark III, is $3,400, and the highest, the EOS-1D X, is $6,800. Even moving to their most expensive non-EOS camcorder, the XF305, you're talking $8000.

In sum, if you think professional DSLR's all cost more than this contraption, you haven't gone looking. Most professional photographers don't drop $20k+ on a Hollywood-level camcorder, and a huge number don't go beyond the ballpark of $6,800 for a DSLR.

Re:costs less than a professional DSLR camera? (0)

Anonymous Coward | about 10 months ago | (#45626127)

The 60D is a consumer camera. Any professional labeling is purely marketing. The only professional EF-S camera is the 7D.

Re:costs less than a professional DSLR camera? (1)

blackraven14250 (902843) | about 10 months ago | (#45626957)

Even the 7D is $1,500, still well below the cost of this setup.

Re:costs less than a professional DSLR camera? (0)

Anonymous Coward | about 10 months ago | (#45625039)

48 rpis = 48 * $35 = $1680

48 cameras = 48 * $30 = $1440

48 piface = 48 * $34 = $1632

48 2gb sd cards = 48 * $8 = $384

48 5V PSU = $48 * 3 = $144

Up to here, it's $5280. Not including:

about half a kilometre of network cable

2 x 24 port switches

1 wireless router

custom laser cut frame

shipping

So let's say $6k. You can buy a nice professional DSLR for much much cheaper than that.

Your cost estimation for this rig is very good this is about a "bullet time camera" (i.e., many cameras) so comparing it to just one camera (as the story submitter did also) is not so applicable.

Re:costs less than a professional DSLR camera? (0)

Anonymous Coward | about 10 months ago | (#45625045)

48 rpis = 48 * $35 = $1680

48 cameras = 48 * $30 = $1440

48 piface = 48 * $34 = $1632

48 2gb sd cards = 48 * $8 = $384

48 5V PSU = $48 * 3 = $144

Up to here, it's $5280. Not including:

about half a kilometre of network cable

2 x 24 port switches

1 wireless router

custom laser cut frame

shipping

So let's say $6k. You can buy a nice professional DSLR for much much cheaper than that.

Your cost estimation for this rig is very good this is about a "bullet time camera" (i.e., many cameras) so comparing it to just one camera (as the story submitter did also) is not so applicable.

Your cost estimation for this rig is very good BUT this is about a "bullet time camera" (i.e., many cameras) so comparing it to just one camera (as the story submitter did also) is not so applicable.
Sorry but i missed that "BUT" in my first reply - slashdot may need a comment re-editing function...

Re:costs less than a professional DSLR camera? (0)

Anonymous Coward | about 10 months ago | (#45627559)

Sorry but i missed that "BUT" in my first reply - slashdot may need a comment re-editing function...

When you submitted your comment, you had to click on "Preview" before you could click on "Submit".
If you had actually previewed your comment, like you should, you wouldn't need a re-edit function.
If you did see an error while previewing, there's a nice big "Continue Editing" button you could have clicked.

Re:costs less than a professional DSLR camera? (1)

Anonymous Coward | about 10 months ago | (#45625091)

Ummm, you can't buy 48 professional DSLRs for that... which is what you would need for the effect.

Yes, you can (1)

dutchwhizzman (817898) | about 10 months ago | (#45625773)

See above, the D70(s) was used by professionals when it was just out. Buy a few broken ones (hey, if you're handy enough to use an RPI, you should be able to fix a card slot soldering problem) and you're in the same price range.

LCD's (1)

phorm (591458) | about 10 months ago | (#45625101)

I'm not sure of the reason for the LCD's. Surely just one LCD for the control unit, or managing from a central PC would work fine.

Re:costs less than a professional DSLR camera? (0)

Anonymous Coward | about 10 months ago | (#45625491)

yes, but you can only buy one DSLR! for that? You need 48 for a bullet time rig!? so that 48*6000 = $28000!

erhhm (1)

fireylord (1074571) | about 10 months ago | (#45627725)

yes, but you can only buy one DSLR! for that? You need 48 for a bullet time rig!? so that 48*6000 = $28000!

Maybe a slight math(s) fail there?

Re:costs less than a professional DSLR camera? (0)

Anonymous Coward | about 10 months ago | (#45629121)

And for all that money, they failed on their goal. The Matrix bullet time effect filmed moving subjects. The results shown were all stationary subjects. Why? Because tight synchronization between cameras is required to make the effect work. Nothing about synchronization was mentioned, so I'm guessing it wasn't done. This is little more than a lame advertisement for a Pi display.

The video didn't really show off the effect (1)

cshay (79326) | about 10 months ago | (#45625001)

People were just sitting still while the camera eye circled them.

To maximize the effect, you should jump in the air to make it obvious you are frozen while the camera circles you.

Re:The video didn't really show off the NIGGERS! (-1)

Anonymous Coward | about 10 months ago | (#45625023)

People were just sitting still while the camera eye circled them.

To maximize the effect, you should jump in the air to make it obvious you are frozen while the camera circles you.

reminds me of a HILARIOUS joke. how do you stop niggers from jumpin on the bed? put velcro on the ceiling!

Re:The video didn't really show off the NIGGERS! (-1)

Anonymous Coward | about 10 months ago | (#45625157)

I thought you just put a rope around their necks and kick the bed out of the way?

Re:The video didn't really show off the NIGGERS! (-1)

Anonymous Coward | about 10 months ago | (#45625227)

People were just sitting still while the camera eye circled them.

To maximize the effect, you should jump in the air to make it obvious you are frozen while the camera circles you.

reminds me of a HILARIOUS joke. how do you stop niggers from jumpin on the bed? put velcro on the ceiling!

LOL!

Must be a software bug (1)

dutchwhizzman (817898) | about 10 months ago | (#45625775)

They forgot to program a time delay in and had all the cameras shoot at the same moment. It will be fixed in the next major release though. ;)

Re:The video didn't really show off the effect (1)

drkim (1559875) | about 10 months ago | (#45631405)

...you should jump in the air to make it obvious you are frozen while the camera circles you.

and handful of confetti works, too.

WTF WHY IS CHILLINGEFFECTS.ORG DOWN? (-1)

Anonymous Coward | about 10 months ago | (#45625019)

how the fuck am i supposed to find good sites to pirate music and movies now?

The videos are cool. (2)

symbolset (646467) | about 10 months ago | (#45625055)

They need to interpolate and time sequence the frames, but that is post processing.

Ah but can you create (-1, Flamebait)

Anonymous Coward | about 10 months ago | (#45625065)

hair and good teeth with a raspberry pi?

A nice idea, but ... inexpensive? (2)

Opportunist (166417) | about 10 months ago | (#45625149)

The idea is great. Especially for stuff like school projects and the like, getting kids involved in computing by giving them the tools to recreate awesome movie effects is, by itself, a nice idea. But we're talking about something where inexpensive is a very relative thing. Of course, compared to the cost of a professional bullet time rig it might be inexpensive. But we're still talking 4-5 digit cost here. Which can easily push the limits for the average hobbyist, let alone something like a school class. I don't know about your classes, but we sure as hell did not have 4 figures to blow on a school project, let alone one that is kinda hard to justify towards some parents.

It remains a nice project, but I guess any halfway decent film maker would probably rather rent some time at a studio equipped with something like that, and everyone else can't blow roughly 5,000 to 10,000 bucks on a toy.

Error establishing a database connection (0)

Anonymous Coward | about 10 months ago | (#45625151)

Oops

Previous art from 1985 (3, Insightful)

ISayWeOnlyToBePolite (721679) | about 10 months ago | (#45625177)

The technique was not invented by the matrix creators. Take a look at this music video from 1985. http://www.youtube.com/watch?v=9el2lg2olpE [youtube.com] (Accept - Midnight Mover)

Re:Previous art from 1985 (0)

Anonymous Coward | about 10 months ago | (#45625933)

simple stop motion... not the same thing at all. Thanks for wasting my time, and introducing me to a shitty "metal" band.

Let me guess, you're a glue sniffer?

Re:Previous art from 1985 (1)

Desler (1608317) | about 10 months ago | (#45625979)

No one claims they did other than a few ignorants. Hell the technique was being used back in the 19th century as well by Eadweard Muybridge.

Re:Previous art from 1985 (1)

jimshatt (1002452) | about 10 months ago | (#45629529)

Please, point me to some of his 'bullet time' work.

Re:Previous art from 1985 (1)

drkim (1559875) | about 10 months ago | (#45631413)

No one claims they did other than a few ignorants. Hell the technique was being used back in the 19th century as well by Eadweard Muybridge.

Muybridge did not do anything like this. He used one camera and had the subjects repeat over and over, taking a shot at slightly differing times.

Re:Previous art from 1985 (0)

Anonymous Coward | about 10 months ago | (#45625995)

Timeslice is a trademark of Time-slice films and Bullet time is a trademark of Warner Bros.

It's the Apple effect(probably tm by now); when you do it there is no previous art, but woe onto any freeloaders trying to ride your coattails after you've done it.

Re:Previous art from 1985 (1)

umafuckit (2980809) | about 10 months ago | (#45626905)

The technique was not invented by the matrix creators. Take a look at this music video from 1985. http://www.youtube.com/watch?v=9el2lg2olpE [youtube.com] (Accept - Midnight Mover)

I feel dizzy now.

Re:Previous art from 1985 (0)

Anonymous Coward | about 10 months ago | (#45628827)

i took a look. it's different. close but different due to limitation of the technoloft available

the technique used in your linked video vs that used in the matrix is the interpolatation to give an apparently seamless rotation around the point of focus
in your linked video, the motion can be easily seen as "jumping" from fixed point to fixed point in a circle, and uses a dark / black backdrop to hide the locations of the fixed cameras
in the matrix, the shot appears to be one continuous motion, and uses a green screen / backdrop to "replace" the fixed cameras in post-shot editing

but otherwise, claiming it's the same thing, your is just a slight adaption of a zoetrope

Gap commercial (1)

BTWR (540147) | about 10 months ago | (#45629289)

I remember seeing The Matrix in the theatres (or even the trailer) and, while Bullet Time was awesome, I thought "Neat! It's just like that Gap ad on tv!"

Gap Bullet Time 1998 ad [youtube.com]

Re:Previous art from 1985 (1)

jimshatt (1002452) | about 10 months ago | (#45629519)

Well, meh. I like the Underwater Love video from Smoke City (1997) way better: http://www.youtube.com/watch?v=0dY1gqTLvhA [youtube.com] (some nice shots at 1:51)

CHDK=much better quality for same or slightly more (4, Informative)

foobar bazbot (3352433) | about 10 months ago | (#45625197)

For each station, we have (priced at Newark):
$40 Raspberry Pi B w/ NOOBS SD card.
$25 Camera module
$34 Piface display/control (seriously? why? aren't they controlled over the network? why aren't they headless? Oh, right: because this whole project is advertisement for Piface, even though their hardware contributes nothing of value to it...)

Making a total of $99 at each station. That's not counting ethernet cable, switches, and for no obvious reason, a separate 5V PSU for each Pi -- I left that out of the per-station cost, because anyone sane would use one power supply for multiple stations.

Now for $99, I can damn sure buy a cheap digital camera for each station, (and an SD card for each of them, if necessary), and have larger sensors, better glass, and crazy features like not being fixed-focus vs. the Raspberry Pi camera module. Sadly, remote shutter is not a common thing on the sort of cheap camera we're looking at, so some hardware hacking (*gasp*) might be required, and many camera models have issues like automatic power off that will make your life miserable -- so for an arbitrary cheap camera, this is better in some ways, worse in others, and not necessarily better on the whole. But with CHDK [wikia.com] , we can beat it easily.

It'd be great if we had $120 a station -- for that money, we can easily rock CHDK. $99 is just on the edge, but I think you can find CHDK-compatible Canons for less (e.g. this one [amazon.com] ; note that other colors are cheaper, but very limited quantity, and without more research, I'm not sure that any of them will actually have firmware revisions supported by CHDK) -- if so, or if we can agree that the combination of better image quality, extra features, and reduced ethernet hardware, is worth a few extra bucks, you should have two options:
1. use USB hubs with CHDK's PTP extensions [wikia.com] to control multiple CHDK-loaded cameras from each Raspberry Pi -- this will allow staggering individual cameras for the true bullet-time effect where the viewpoint revolves around a slow-motion (not completely frozen) subject, as well as the all-at-once mode described in TFA, and any combination.
2. forget the Raspberry Pis, and control the cameras using CHDK's USB remote shutter [wikia.com] capability -- this is very simple in the all-at-once case, as you can simply wire 48 USB ports to a single 5V PSU, and switch it on and off. The proper effect is a little more complicated, but still no-CPU-required, e.g. use a single debounced pushbutton to generate a pulse, and clock source + a half-dozen 8-bit shift registers to sequence that pulse to all 48 USB cables. Or use a microcontroller with those shift registers to generate the pulse and the clock -- by varying the clock, you speed/slow the ratio of subject motion to viewpoint motion. Or use a microcontroller with enough GPIO to control all the cameras directly.

Re:CHDK=much better quality for same or slightly m (3, Interesting)

ebenupton (2424660) | about 10 months ago | (#45625637)

If I were building this rig, I would have used the $40 Model A+camera bundle for a cost-per-node of ~$50 including a USB Ethernet adapter and an SD card per node and a decent PSU shared between four nodes.

A bigger issue looking at the videos is the need to equalize the AGC setup (easy) and color temperature correction (harder) across the modules. Perhaps shoot RAW and then fix it with post-processing? This is where the CHDK alternative, with it's better optics and lower sensor variability, really wins out. Plus you'll have Christmas gifts for all your friends and family once you take the rig apart :)

Re: CHDK=much better quality for same or slightly (1)

UglyMike (639031) | about 10 months ago | (#45625659)

Last remark of Eben is very important, I think. When you're finished playing with the matrix effect ( and yes, they should really think of photographing something more dynamic - people jumping, water splashing, fireworks, etc) you simply store that wooden frame and build the 3d people scanner (I would love to have a 3d print of my daughter, my wife,...). Finished with that? Store the wooden frame next to the first one and come up with something else to do with your 48 Raspberry Pies. After all, each of them is a full-fledged, if somewhat underpowered, PC.

Re:CHDK=much better quality for same or slightly m (1)

fa2k (881632) | about 10 months ago | (#45625811)

Cool ideas, seems like a more sane design (some people get hung up on RPi, "when all you have is a dick, all problems look like assholes"). Couldn't you wire all cameras with USB to a single computer via some hubs? There may be some latency in issuing the "take picture" PTP commands, but it seems like with a computer you could 1) define the delays arbitrarily in software and 2) load all the pictures immediately, saving you from reading 48 SD cards.

Re:CHDK=much better quality for same or slightly m (1)

itsdapead (734413) | about 10 months ago | (#45625817)

Now for $99, I can damn sure buy a cheap digital camera for each station, (and an SD card for each of them, if necessary), and have larger sensors, better glass, and crazy features like not being fixed-focus vs. the Raspberry Pi camera module.

Except, after every run, you'd have to extract the SD cards from each camera and download them one-by-one to a PC to turn into a movie. With this, you can download all the images over the network in a few seconds.

Anyway - you weren't listening to TFA: this idea is primarily aimed at schools & colleges that already have or want class sets of Pi's for teaching programming and computer control, and the idea is that students will get involved in the programming to make it all work. As others have posted before: when you've had fun with this you tear it apart and use the Pis for the next project.

As for the boring videos: having kids moving or throwing things without 15cm of woodchips on the floor and padded helmets would probably waken the dreaded Safety 'Elf. Hopefully they had some actual fun in the clips that didn't get published on the internet. Actually, having a bunch of kids practicing scissor-kicks in the workshop does sound like an accident waiting to happen...

Re:CHDK=much better quality for same or slightly m (1)

foobar bazbot (3352433) | about 10 months ago | (#45626493)

Except, after every run, you'd have to extract the SD cards from each camera and download them one-by-one to a PC to turn into a movie. With this, you can download all the images over the network in a few seconds.

Yeah, I'm pretty sure I mentioned that without CHDK it's definitely not an improvement in all ways. Note that the first CHDK option does permit automatic image retrieval* over the network, and even if you go with the second one, or with non-CHDK cameras, I'd just walk around with a laptop and a USB cable, plugging it into each one, let a script automatically mount/copy/umount, then unplugging it -- not only is the USB port typically more accessible than the SD slot (and if not, I've already got a cable in it for the remote-shutter, so I can break in at the other end of that!), but this way I don't risk cameras mysteriously swapping UUIDs because somebody mixed up the SD cards. It's still a fair bit of work, but given that the point of the rig is a cool tech demo you fire up once rather than a tool you use routinely, I don't see it as prohibitive -- once you get it working, you can take quite a number of pictures before you have to do the USB run-around and "develop" the results.

* As another poster suggested, you might be able to form a 3-level tree of 4-port hubs, connecting all cameras to one computer and skipping the network entirely -- not sure if latency would be a problem or not, but you can certainly connect a few to each of several networked nodes, and use the network to transfer files to a central location.

Terrorism (3, Funny)

rebelwarlock (1319465) | about 10 months ago | (#45625643)

It has the word "bullet" in it, and you can make it at home? Prepare to hear the sweet music of militarized cops breaching your front door.

Creative? (2, Insightful)

wonkey_monkey (2592601) | about 10 months ago | (#45625707)

A team of extremely creative people

Extremely creative? Not really.

Raspberry Pis achieved the Hollywood's 'frozen time' effect at a much lesser cost.

And much lower quality! And without doing any of the time consuming post-processing that's required for an actual film!

I still think it's cool - or I expect I would if the site was working - but go easy on the hyperbole.

Re:Creative? (0)

Anonymous Coward | about 10 months ago | (#45626793)

And yet every non-functional blob of fragile plastic some idiot 3D prints at home is the harbinger of Humanity's Glorious Third Revolution and Doorway to the Galaxy.

Server? (2, Funny)

Anonymous Coward | about 10 months ago | (#45625813)

Must be running their server off a Raspberry Pi as well...

Multicam from ReelEFX (3, Interesting)

Anonymous Coward | about 10 months ago | (#45625991)

Ok. I was one of the people building one of the first computer controlled multi camera rigs (http://www.reelefx.com/index.php?c=multicam.list) , so here's some background info to put this into context:

Multiple cameras triggered to capture motion is older than the movies. Eadweard Muybridge did it.
There were several people who built "one long strip of film with multiple simultaneous lenses and shutters" rigs in the 90s (one was a bunch of inexpensive cameras with the backs removed and a single long piece of film)

The famous GAP "swing dance" commercial was done by convention rotoscoping/animation: they filmed from various angles, and built 3-d models and texturemapping/morphing.

We did our camera rig for a commercial directed by Tony Kaye using Andre Agassiz, where he wanted the POV of the camera to track the tennis ball as it went down the court. And Tony Kaye didn't want to do it with visual effects (film the ball separately from the crowd, and composite it). So we built a rig with 100 cameras, carefully timed to fire as the ball went downcourt. Andre can hit the ball at the same speed every time without any problem, so it's just a matter of triggering the sequence by hand at the right time. Since they're standard 35mm film cameras with standard 36 exposure loads, you get 36 takes before you have to reload 100 cameras. Then, in post production you take frame 1 from camera A, frame 1 from camera B, etc.and string them together.

The cameras were fired by a bunch of digital I/O cards in a rack mounted PC, and frankly, that was a nightmare. Miles(literally) of cables and connectors. Those Rpi folks learned that lesson too.
There have been tons of commercials and movies that have used that rig and subsequent versions.
There's really cool stuff you can do: fire the cameras at a varying rate to essentially create any motion profile you want; use cine cameras to allow intercutting motion frames with the still frames, etc.

So here's what the RPi folks (or followers) will find:
1) Cameras are not identical, particularly in terms of the color of the lens. Your eye automatically will compensate for an overall color cast, particularly on multiple pictures from the same camera, or when you get the film turned into prints, they adjust to grey or skin tones. But in real life, modern camera lenses made of plastic (which are high optical quality, and can be made aspheric, which helps) have slight color casts that vary from camera to camera, and when you start making composites of frames from multiple cameras, it's really obvious. So you have some post processing to do.
2) Camera shutters have a lot of timing uncertainty. Back in the mechanical shutter days, we found that the microprocessor inside the camera (Canon EOS) had a polling loop looking at the shutter release button. A polling loop with 50 ms cycle time probably isn't noticeable to the casual user, but it's very noticeable when you're taking multiple shots of an object moving at constant speed. We wound up modifying cameras
3) the optical geometry of the cameras is not consistent. So that adds another step in post production and calibration of all the cameras ahead of time.

The big one is interconnections. The 100 parallel cables is a deployment nightmare, keeping track that camera 1 is plugged into cable 1, etc. For the second iteration, we built a microcontroller inside the camera to replace the original camera controller, and set up a daisy chain approach with individual ID numbers. Then the master just sends messages saying "camera N, you fire at time T1, T3, T4", and a master sync signal goes to all cameras. Lots less cable. Subsequently (I don't work there any more) they've gone to digital cameras, which is a post production godsend. Pulling 100 rolls of film and keeping them straight (you have to slate each camera individually, so the strips are identified), then scanning them for post, then doing all the corrections, and allowing for the inevitable "skipped" or "extra" frames was a nightmare. And you got to do that overnight so the director could see the rushes/dailies the next morning.

Much easier to get a file with all the frames in it.

If you're running at 100fps (typical.. most of these things want to have some degree of slo-mo), you need to time the shutter to fractions of a millisecond (even if the shutter speed/exposure length is 10 milliseconds).

There's also some artistic things. Humans expect some degree of motion blur, so you need to make sure that the shutter speed matches the apparent motion rate. If you use real short shutter speed, the resulting footage has a "stroboscopic" look which is very unnatural, so unless you want that, you need to add blur. These days, you can add blur in post pretty easily, though.

Dotted (1)

koan (80826) | about 10 months ago | (#45627643)

"Error establishing a database connection"
Another hobbyist nuked.

Re:Dotted (0)

Anonymous Coward | about 10 months ago | (#45630717)

See the page from Google's cache:
http://webcache.googleusercontent.com/search?q=cache:http://www.muktware.com/2013/12/create-bullet-time-camera-rig-raspberry-pi/17234

bullett time (0)

Anonymous Coward | about 10 months ago | (#45628337)

I'm changing my time zone to Bullet Daylight Savings Time.

bunch of haters (0)

Anonymous Coward | about 10 months ago | (#45685559)

while your sitting around your desk, critiquing someones work...try look around and tell me what the last thing you created was...a hot pocket pizza maybe, cholesterol, high blood pressure, jiz stains?

Give this guy some due credit...he went out on a limb in order to help teach students to use new tech in ways not done before. Can you get better fx with better equipment...of course! He knows that.

Can a school bust out money for 40dslrs & matching lens...probably not while they are laying off teachers and having furlough days.

BTW math studs, 40xDLSRS rigs >>>>> 40pi rigs. yea a 7d costs around $1500 (with no lens) but do you want to buy 40 of them?

Calm down nerds and quit hatin!

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