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There oughta be a bullet time video booth

there.oughta.be

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Re: There oughta be a bullet time video booth

#51
post #13

This type of photo/video booth is widely available for rental these days.

I just looked them up and you are right. It varies from 5 cameras to hundreds of cameras. Interestingly though, I haven't seen any of them demo the continuous rotation through a wall effect that Sebastian shows here though which kind of makes the professional solutions feel like they have some room for improvement.

Re: There oughta be a bullet time video booth

#52

That camera had an MSRP of $899 when it was new in 2006 [0]. Amazing that they now sell for only £50, and still take fantastic pictures even by today's standards [1]. Technological progress is nothing short of remarkable. [0] https://kenrockwell.com/canon/rebel-xti.htm [1] https://onfotolife.com/camera_sample_photos?camera_id=30&pag...

For anyone who is interested in older cameras I use a Canon Rebel T3i as a webcam and it works fantastically. In 2020 because of you-know-what Canon released a webcam driver for a bunch of their cameras and the T3i is one of the oldest ones supported (the most recent version of their driver drops support for this camera but older drivers work just fine). Paired with an AC power adapter and a mount for my monitor it's…

For anyone that might also already have a Nikon D5100 or D7000 to repurpose as a webcam, you can use a custom firmware[1] to clean up the HDMI output, an HDMI capture card and OBS to fix the aspect ratio. That's the setup I use.

1: https://nikonhacker.com/wiki/Supported_Models

Re: There oughta be a bullet time video booth

#53
Related topic, wiggle stereoscopy: https://en.wikipedia.org/wiki/Wiggle_stereoscopy

And there was a lens for this kind of effect, it allowed capturing three images at once [1] [2].

There were also dedicated cameras [3].

> Using its four lenses, four images from slightly different viewing angles were taken simultaneously. With the individual images half the size of the usual 35mm image frames, each 3D photograph taken used the space of 2 full 35mm exposures on the film. So a roll labeled as "36 exposures" would yield 18 3D pictures with four images each.

[1]: https://www.dpreview.com/news/1238704821/this-3d-printed-len...

[2]: https://www.georgemoua.com/store/d9000-fe-3d-stereoscopic-wi...

[3]: https://en.wikipedia.org/wiki/Nimslo

Re: There oughta be a bullet time video booth

#54
post #6

He's using digital single-lens reflex cameras with moving mirrors in an application where you don't need that, but do need a good camera. What do you use today when you need a good camera with no user interface?

define good camera. it's a bit weird because it often turns out that cameras with user interfaces are cheaper because of economy of scales. that being said, a market for almost barbone sensors on pcb's seems to be building and is lead by raspberry pi's camera modules, where the hq module has a reasonably sized sensor but is still a far cry from mft, aps-c and full frame sizes. the hq camera is almost on parity with m…

Yes, this is related to the complaint that webcams tend to be lousy cameras, for no good reason.

Re: There oughta be a bullet time video booth

#56

That camera had an MSRP of $899 when it was new in 2006 [0]. Amazing that they now sell for only £50, and still take fantastic pictures even by today's standards [1]. Technological progress is nothing short of remarkable. [0] https://kenrockwell.com/canon/rebel-xti.htm [1] https://onfotolife.com/camera_sample_photos?camera_id=30&pag...

For anyone who is interested in older cameras I use a Canon Rebel T3i as a webcam and it works fantastically. In 2020 because of you-know-what Canon released a webcam driver for a bunch of their cameras and the T3i is one of the oldest ones supported (the most recent version of their driver drops support for this camera but older drivers work just fine). Paired with an AC power adapter and a mount for my monitor it's…

Mileage varies between cameras, but one small warning to anyone considering this if they spend even a couple of hours a day in meetings with the camera on from time to time - the sensors in some DSLRs/mirrorless models can overheat while live streaming and your video will cut out.

Most of them were only specced to record up to 30 minute clips at a time in original guise and are passively cooled, so running for an hr or more can push the sensors beyond their original specifications etc. I've had this happen rarely with some m43 cameras I use as webcams via an HDMI capture card. There's a ton of youtube videos on this topic with all sorts of homemade cooling setups:

> https://www.youtube.com/watch?v=1IMSWWccQwQ

Re: There oughta be a bullet time video booth

#58

> In case you never heard of it: The bullet time effect was famously introduced with the movie “The Matrix” from 1999. actually I think one can already see it in this ad from 1996: https://www.youtube.com/watch?v=qbOGJy3P6rA

I always assumed this was pioneered by Hong Kong action cinema?

Re: There oughta be a bullet time video booth

#60
The challenge here is cost. You need 20-40 perspectives at ~$1000 bucks each including the camera body, lens, trigger system, remote download, and output pipeline. So a hand built cost optimized system will cost $20k - $40k in hardware. Operating is also kinda painful: calibration of each camera is required every time the rig is moved or exposure is adjusted and all shots must be designed ahead of time. It's just kinda a limited market due to the complexity and cost.

Neural Holography should arrive to market within the the next 6 months, which will allow for any frame to be seen at any angle with as few as 20 cameras for 360° x 180° coverage, allowing for bullet time shots to be designed after the fact with the added bonus of having cinematic quality 3D live action content for use in VR and other 3D environments.

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