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Using the railway network as a flatbed scanner

philo.gay

71–80 of 81 posts

Re: Using the railway network as a flatbed scanner

#72
One fun thing is that the camera is that the projection is perspective in the vertical axis and othographic in the horizontal axis. That's why "zooming out" is done by squashing the image horizontally.

Imagine taking a picture with a regular camera of a person nearby and a statue 16x times as large but 16x further away. Both figures would have the same apparent size: they would show up as the same number of pixels in width and height. However, with a line scan camera, the apparent width of objects does not change with distance. Those same objects would have the same apparent height, but the width of the larger statue would be 16x.

Re: Using the railway network as a flatbed scanner

#74
Very cool. I'm surprised that it is so hard to stitch the frames together, and requires acceleration data. Naive I guess, but I was imagining you could simply examine the frames and work out how to join them nicely in code.

It'd be cool to see some ridiculously wide, scrollable images from this process.

Re: Using the railway network as a flatbed scanner

#77
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".

I see a blank page with the tab title "S L I T S C A N S P A ...". Scrolling does nothing. What's supposed to be there?

Re: Using the railway network as a flatbed scanner

#78
post #77
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".

I see a blank page with the tab title "S L I T S C A N S P A ...". Scrolling does nothing. What's supposed to be there?

If you have a camera and give it access to use it then it will work as a slitscanner. At least that's what happens on my laptop...

Re: Using the railway network as a flatbed scanner

#80
post #18

I've posted this here before but I have been creating animations using a similar process with a regular camera and manually splicing the frames together. [1,2,3] The effect is quite interesting in how it forces focus on the subject reducing the background into an abstract pattern. Each 'line' is around 15px wide. I think I went through exactly the same thought process as the author, funny how ideas can come up indepe…

Had to think for a moment to understand the "Tokyo enters the dark night" shot.

Very beautiful and very clever. Loved it.

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