Raspberry Pi Tacho Projector Bike Fake?

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5 pointsUchikoma5 comments

I looked at that project and found it very cool.

Then I was confused, e.g. at 2:29 (and in some places before) the projection against the car doesn't look right. Is it fake? Is it not projected to the ground and I'm misunderstanding the project?

When looking from exactly behind a projector, the image will always look the same, no matter what it's projected against. The 1st person view is from very nearly behind the projector, so I would expect very little distortion, I would expect it always to look like a circle with a number in it. From that point of view, this looks totally reasonable.

After some more thinking:

At 2:29 or 2:22 where it is projected to the bottom of a tire, the light reflected seems evenly reflected, while it should not depend on the background color (black) but on the angle it hits the tire. So I again tend towards this being fake.

Doesn't look wrong to me, but I'm not an expert.

Good point.

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