EEVblog #857 - High Speed Camera Fun - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: March 04, 2016, 10:52:55 pm
content: Dave plays with his new Sony RX100 Mk4 high speed camera that can shoot 1000fps.Blowing up capacitors, fuses, and LED's.And what does a multiplexed VFD display look like?

author: photon
author_rank: Frequent Contributor
timestamp: March 04, 2016, 11:54:18 pm
content: Beauty.

author: hopski
author_rank: Regular Contributor
timestamp: March 05, 2016, 12:11:14 am
content: Tasty. Some of those older electrolytics with no vents do tend to go with a good bang.I've done a few "accidentally"

author: nctnico
author_rank: Super Contributor
timestamp: March 05, 2016, 12:46:24 am
content: This video reminds me of this guy making stills of all kinds of rapidly moving objects and splashes using self build circuits:https://www.flickr.com/photos/fotoopa_hs/albums

author: nidlaX
author_rank: Frequent Contributor
timestamp: March 05, 2016, 01:06:17 am
content: The RX100 IV is a beast of modern engineering. Sensor and processing tech consumers couldn't even dream up 5 years ago.

author: strangersound
author_rank: Regular Contributor
timestamp: March 05, 2016, 01:23:48 am
content: The multiplexed VFD was definitely cool.Quote from: nidlaX on March 05, 2016, 01:06:17 amIt is amazing what the average guy can get his hands on these days. I'm still amazed at what my Lumix can do and it's already old news now.

author: EEVblog
author_rank: Unknown
timestamp: March 05, 2016, 01:52:43 am
content: Quote from: nidlaX on March 05, 2016, 01:06:17 amIt's still no where near enough for shooting most things.Explosions for example are not much good at 1000fps, it's basically there one frame and gone the next.At least for small scale. Big scale mythbusters style it's enough.

author: nidlaX
author_rank: Frequent Contributor
timestamp: March 05, 2016, 02:03:18 am
content: Quote from: EEVblog on March 05, 2016, 01:52:43 amYeah! Are you thinking of what happened in Mike's latest video with the GFCIs? If you're gonna risk blowing yourself up, better get a camera that can grab the moment!

author: pickle9000
author_rank: Super Contributor
timestamp: March 05, 2016, 03:14:23 am
content: Chinese multimeter and a brick.

author: Georgitsu
author_rank: Newbie
timestamp: March 05, 2016, 06:40:04 am
content: Cool! I love seeing the fuse filament ball up at its end where it melted.Couldn't help but notice the bright sunny day as he blew up the caps outside. We're still wintering over here in the states.

author: 6581
author_rank: Unknown
timestamp: March 05, 2016, 07:17:37 am
content: Quote from: pickle9000 on March 05, 2016, 03:14:23 amI don't like seeing anything useful smashed to pieces. But hopefully the brick will survive just fine.

author: pickle9000
author_rank: Super Contributor
timestamp: March 05, 2016, 07:22:32 am
content: Quote from: 6581 on March 05, 2016, 07:17:37 amI love bricks.

author: fantis1337
author_rank: Contributor
timestamp: March 05, 2016, 08:24:57 am
content: Someone should make a hour long high fps video of caps blowing up with some meditation music in the background. Found that oddly relaxing.

author: German_EE
author_rank: Super Contributor
timestamp: March 05, 2016, 10:40:31 am
content: Head over tohttps://www.youtube.com/user/RODALCO2007where 90% of the content is stuff being blown up. Not my taste but YMMV.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 05, 2016, 10:50:21 am
content: Does the Sony have a post or mid-trigger mode so you can stop it after the event?

author: BobC
author_rank: Unknown
timestamp: March 05, 2016, 07:05:33 pm
content: In 2000 I was working at a high-speed industrial camera company on a team to build an extremely ambitious device: A camera that could take video at 100,000 frames per second while being subjected to 100G forces. We wanted to eliminate film from the industrial market, where so-called "streak" cameras could have frame rates up to 1,000,000 frames per second (most famously used to record nuclear bomb tests).Being an embedded real-time software engineer, my job was to define and implement the interface layer between the low-level camera hardware and the external high-level user interface. The camera hardware was a fiercely complex dynamic state machine, while the user interface exposed many controls that could easily interfere with each other (the range of paramater X depended on the settings of parameters Y and Z, each of which depended on A, B and C).My solution was to get the hardware engineers to implement a "what if" capability, where the camera would return an error rather than silently accept an invalid setting. This capability allowed both the low-level hardware and the user interface to evolve almost independently, while my middle-layer tracked two whole-camera states: The last successful configuration, and the last unsuccessful configuration, where the differences were made available to the UI.But who cares about software?When our first all-up alpha camera was built (electrically correct, but quite unable to fit in the final enclosure), the first high-speed video run (at 85K fps) produced all black frames when pointed out the window at a brightly sun-lit outdoor scene. The hardware folks were going crazy, thinking we had failed to correctly read the pixels from our custom sensor.I sat back and did the math, calculating the number of photons needed to reach half-exposure on a pixel, then dividing by the exposure time to get the required flux. That flux level was enormous. About 30% of what pointing the camera directly at a full-field view of the sun would yield. Something we were not about to do, since we didn't want to melt the sensor in our first working prototype.But what other bright light source could we use? In our conference room was an early DLP video projector that used a high-pressure gas-discharge tube mounted behind an IR filter. We aimed the camera through the filter and directly imaged the arc in the lamp, clearly showing how it danced within the confines of the bulb.We immediately posted the video to our website, and just a few days later the US President of a Very Large Japanese projector manufacturer called, wanting to see our prototype camera in action.It turns out that this 'arc wander' was a serious problem for projector manufacturers, since it meant the optical focus had to encompass the entire arc volume, rather than just a central portion. In many projectors of the day, this effect was visible in the projected image as a quiver or shake leading to a soft-defocus effect. One corrective approach had been to make the bulbs smaller, but that made it much more difficult to remove the generated heat, leading to greatly reduced bulb life.By the time the Japanese delegation arrived, we had the first of three beta units built. We repeated our experiment for them, using bulbs they had brought with them. On the spot, they offered us an insane price for one of our beta units, wanting to leave with it that day. We made them wait until all three beta units were ready, then sold them one.The beta units did fit in the final enclosure, but they didn't come close to meeting the 100G impact requirements. Why would any camera need to survive 100G treatment? That's more than enough force to tear any lens right off the front of the camera. Our design goal was for our camera to survive a lifetime of such impacts without affecting normal operation (aside from having to replace the lens).Our camera had two main customers: First was the auto crash test industry, where they needed cameras to be inside cars during high-speed crashes. The second was military weapons testing, where the closer the camera could be to the blast, the better the video would be.Once such high-speed video was available, some of the spin-off uses surprised us. For example, one customer used our video to greatly improve the state-of-the-art in Finite Element Analysis of structures, improving their analytical techniques until the simulation of an impact precisely matched the actual deformation captured by our cameras.Unfortunately, the development costs for this camera bankrupted the company: The expected pre-orders failed to appear (there was a recession at the time), while our lines of credit became too expensive to afford. The company was sold to a competitor for a song, and the entire engineering team was laid-off just weeks after the camera work was completed.

author: halexa
author_rank: Regular Contributor
timestamp: March 05, 2016, 08:15:35 pm
content: Hey Dave,Time to revisit the sparkgap video in high speed.

author: electr_peter
author_rank: Unknown
timestamp: March 05, 2016, 10:31:41 pm
content: I have considered to buy Sony RX100 Mk4 for it's high speed capture capabilities but did not do it after all.I thought about my needs and found 1000 fps to be not good enough, because:1000 fps (= 40 * 25 fps) is only 40 times faster than normal playback - it is not enough to capture more interesting events invisible to a naked eye. 400-1000 times or faster (10000-25000 fps) would be more suitable1000 fps mode is limited in resolution/recording speed/lighting conditions/focusing/frame size/... Special setup with lighting and some sort of quick triggering mechanism is needed to use short memory - not that trivial with this camera.Sony RX100 Mk4 is a great camera, but it is very expensive if 1000 fps option is not used/usefull for you.

author: joeqsmith
author_rank: Super Contributor
timestamp: March 05, 2016, 11:40:49 pm
content: Quote from: mikeselectricstuff on March 05, 2016, 10:50:21 amIt can buffer up the data so when you press the record it stores everything prior to that. You can also trigger before the event.Video showing the external trigger I modified for it to except a standard 50 ohm source.Spark plug with Sonyhttps://www.youtube.com/watch?feature=player_detailpage&v=RZJJQVxvceM#t=93

author: EEVblog
author_rank: Unknown
timestamp: March 06, 2016, 12:55:09 am
content: Quote from: mikeselectricstuff on March 05, 2016, 10:50:21 ami found it has a stop trigger mode, but haven't tried it yet.Annoyingly the remote WiFi trigger app doesn't work in HFR modeSo you have to press the annoying little fiddling stop button on the camera.

author: EEVblog
author_rank: Unknown
timestamp: March 06, 2016, 12:56:32 am
content: Quote from: halexa on March 05, 2016, 08:15:35 pmYep, I'll try that.

author: McBryce
author_rank: Super Contributor
timestamp: March 06, 2016, 01:53:00 pm
content: Try watching solder paste in the moment the tiny spheres turn to liquid. Really cool if you can get the magnification and slow-motion.McBryce.

author: rsjsouza
author_rank: Super Contributor
timestamp: March 07, 2016, 03:01:30 am
content: Great video, Dave. Perhaps a tantalum capacitor would also be interesting as it would go down in flames or with a *BANG!*Quote from: EEVblog on March 05, 2016, 01:52:43 amThat Sony is a beauty, alright. Would love to have one.Mythbuster-level, however, is another league: yesterday I watched one of Mythbusters' episodes of their last season, and they were using a 28k fps full HD camera!

author: 67mustang-man
author_rank: Newbie
timestamp: March 07, 2016, 08:45:31 pm
content: I have a power supply similar as that one, Branded Tenma, I do often wonder how well they are built. Great video!

author: lemming
author_rank: Contributor
timestamp: March 15, 2016, 11:12:51 am
content: Hi All,I have been looking at this camera as I have an earlier one (Nikon 1 AW1) that does 400 fps and 1200 fps, but the resolution is pretty tiny.What might interest you guys though is what we use it with....http://imgur.com/a/gZZCY

author: encryptededdy
author_rank: Frequent Contributor
timestamp: March 18, 2016, 11:55:56 am
content: Quote from: EEVblog on March 06, 2016, 12:55:09 amLatency is probably 1/4 of your recording time; it's impractical.