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I took this shot using a Sony Xperia SP with OpenCamera, here are some details:

  • Exposure: 1/800
  • ISO: 50
  • Aperture: f/2.4
  • focal length: 3.0

The photo was taken out of a train, at around 160km/h, the truck was moving in the opposite direction with approx. 90km/h.

The distance that the truck moved withing the 1/800th of a second should be somewhere around 10cm (~1/3 foot), but the distortion is clearly higher. It also does not look like it's related to the lens distortion as the it's speed dependent (look at the car and guardrail as a reference).

This looks similar and is caused by line-wise image creation of a crt-tube. Could it be that the sensor is reading the pixels line-wise as well?

Almost forgot the most relevant detail: the shot was taken on the Storebæltsbroen. ;-)

Distortion

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This is a prime example of the so-called "rolling shutter" effect. It happens in some devices (like this phone) that do not have physical shutters and have to expose the image line by line. What's observed here is an image exposed from top to bottom, i.e. the top part of the truck trailer was exposed a certain amount of time earlier than its bottom part, that's why it appears skewed.

This is not caused by the shutter speed you used but rather by the way the sensor exposes the image. If it was because of the shutter speed, the whole trailer would've been blurry.

Wikipedia article on the subject.

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  • \$\begingroup\$ Interesting... I would say the shutter speed of 1/800 seconds was exceeded then, looking at the deformations and making an estimate of the speed difference between the truck and train. \$\endgroup\$
    – Orbit
    Dec 29, 2017 at 22:21

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