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Using the railway network as a flatbed scanner

philo.gay

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Re: Using the railway network as a flatbed scanner

#41

Post by russdill »

ggerules wrote: post #37

Taken to the extreme.... I gotta wonder. Owen from RanOutOnARail could make some incredible wide pictures from his journeys if he had this setup. Been watching his YouTube channel for years [0], [1]. He has a Patreon account with more videos [2]. He use to have a lot more videos on YouTube. It's illegal to ride trains the way he does, but his videos helped get me through the long time of the covid pandemic after I wo…

Taking this to the extreme is doing this from space, which is how many imaging satellites actually work.

Re: Using the railway network as a flatbed scanner

#43

Post by xoxxala »

4gotunameagain wrote: post #9
wkjagt wrote: post #7

Earlier quoted context omitted.

Do you think you'd be able to find this post (assuming it's still up)? Would love to see it.

https://www.sentex.net/~mwandel/tech/scanner.html

Thanks for posting that. The picture of the garage door opening is a trip!

Re: Using the railway network as a flatbed scanner

#44

Post by zipy124 »

crote wrote: post #39
mhb wrote: post #16

Lynx photo finish cameras. Same idea: https://www.finishlynx.com/

Line scan cameras are (were?) also very common in industrial applications. It is the best way to take images of objects on a rapidly-moving conveyor belt as you don't have to be worried about blurring due to long shutter times, and you can achieve incredible frame rates. The downside is that they are highly specialized (in other words: expensive) and require knowledge of the belt speed to reconstruct a proper image.…

still incredibly common. The key is that they give you very low latency information since you get it line by line. They're not too expensive tbh and getting speed data is not too difficult.

I've used modern high-speed cameras (>10k FPS in real-time streaming) and they just don't come close currently. Mainly an interface issue. There are some DMA/frame card alternatives but they haven't overtaken the market yet.

Re: Using the railway network as a flatbed scanner

#45

Post by strohwueste »

namibj wrote: post #34
strohwueste wrote: post #17

Great writeup! Planned doing the same thing Herr in germany. Thought a Smartphone camera would be enough but there no way to access the camera2 api for those highspeed recordings. I took 1h long 240hz 4k vertikal videos (out of the Schwebebahn in Wuppertal) which could be displayed by MacOS preview. Right no im waiting for a good gaussian splatting tool to create the driving of the "Train” in Blender. The newest Ling…

Ohhh, nice; happy to have a chat on the subject; suggest a messaging option to discuss further if you're interested. Check out keybase on my profile for some listed contact options; you can also use the padlock symbol in the menubar there to PGP encrypt a message to me and share that through any suitable channel that can handle that ascii. Edit: I've captured and extracted-to-textured-mesh Mirker Bahnhof before it go…

Well havent tried to do IMU rading& GPS while doing highspeed recordings. But maybe thats the fix. But also as a goal i would see to do the ICE from Hamburg to Munich as it is the longest with 8h but while 300kmh the 240 fps of a phone isnt enough and a linescan camera would be needed again. And the window (quite literally) is closing as the new ICEs have those New meshes inside so you cant take the Video without those... Also the data requirements of an 8h 4k 240Hz/480hz video are a bit scary

Re: Using the railway network as a flatbed scanner

#48

Post by focusedone »

jonty wrote: post #11

If you want to play around with slit scanning, I made this little toy a number of years ago and frequently find myself using it on trains: https://slitscan.space Press and hold your phone screen to switch between the front/back cameras, or hit "c" on a computer. Tapping the screen saves the image, as does "s".

This is super cool!
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