Porsche Cayenne stroboscopic effect

[Costas Athan]

What the title says.

https://www.youtube.com/watch?v=BzWeDvwO1-k&hd=1

The wheels of a Porsche look stationary as the car moves forward at high speed. I think it is kind of cool that the frame rate of the camera and the rotational speed of the wheels happened to be appropriate to create this illusion, so I uploaded the video on Youtube!

 

[DominionSeraph]

Why thank you for this shadowed and barely-visible example of this ridiculously common phenomenon.

 

[Costas Athan]

Why thank you for this shadowed and barely-visible example of this ridiculously common phenomenon.

You don't have to thank me. And it's not so common to see a wheel stationary. In most cases you see it turn backwards. In order for it to appear stationary the frame rate must be an integer multiple of the wheel's rotational speed.

edit: By the way if you can't see it, watch the video in 1080p and fullscreen. You will definitely see it then, especially when the video plays in slow motion.

 

[soccerballtux]

Let me introduce you to my friend mr nyquist,,,

 

[MagnusTheBrewer]

I watched it three times before I noticed anything but the film car driving like an asshole.

 

[Costas Athan]

Let me introduce you to my friend mr nyquist,,,

You remind me some courses related to Signal Processing.

 

[Costas Athan]

I watched it three times before I noticed anything but the film car driving like an asshole.

You figured that out from 3 seconds of driving? You are a great judge.

By the way, focus on the wheels and you'll see the stroboscopic effect immediately.

 

[FuzzyDunlop]

You figured that out from 3 seconds of driving? You are a great judge.

By the way, focus on the wheels and you'll see the stroboscopic effect immediately.

It appears that you forced the oncoming car to move over the to shoulder quite a bit. THis is in Greece right? Is this a legal pass there? Cant tell if there was more than one lane in each direction.

Anyways, yes, i see the effect. Cool.

 

[MagnusTheBrewer]

You figured that out from 3 seconds of driving? You are a great judge.

By the way, focus on the wheels and you'll see the stroboscopic effect immediately.

He passes another car one a one lane highway crossing the center line and couldn't even bother to time it so he didn't endanger the oncoming car. That sir is driving like an asshole.

 

[DominionSeraph]

I watched it three times before I noticed anything but the film car driving like an asshole.

That's perfectly normal in parts of Europe -- you turn on your blinker, the person in front of you will move over, and the oncoming traffic will move over as well.
Americans can't even navigate a 4-way stop, so it's not surprising they can't work out that maneuver.

 

[Costas Athan]

It appears that you forced the oncoming car to move over the to shoulder quite a bit. THis is in Greece right? Is this a legal pass there? Cant tell if there was more than one lane in each direction.

Anyways, yes, i see the effect. Cool.

It is in Greece. There is a broken line so yes, it is legal. You can overtake a car using the opposite direction of the road if the line is broken. This applies worldwide! There is one lane, but the Cayenne moved kindly to the shoulder to make me some space. I touched the pavement markings in the middle of the road, only with my left wheels.

He passes another car one a one lane highway crossing the center line and couldn't even bother to time it so he didn't endanger the oncoming car. That sir is driving like an asshole.

Watch the whole video from 9:09 when I approach the Cayenne till 11:10. There were big waves of oncoming traffic. I think I timed it well enough. The last wave before the overtake is on 10:50. The Cayenne moved to the shoulder and made me enough space to pass it. As you can see on 10:50 two cars can easily fit on the same direction. There is a car next to an 18-wheeler!

 

[Ferzerp]

I guess this one is right up there with your "OMG DRIVING THROUGH A MONSOON!" post which failed to deliver.

It was a drizzle.

 

[Costas Athan]

I guess this one is right up there with your "OMG DRIVING THROUGH A MONSOON!" post which failed to deliver.

It was a drizzle.

I love how everyone can't stay on topic!

 

[DominionSeraph]

I love how everyone can't stay on topic!

This is The Garage, not Digital and Video Cameras.

 

[Costas Athan]

It appears that you forced the oncoming car to move over the to shoulder quite a bit. THis is in Greece right? Is this a legal pass there? Cant tell if there was more than one lane in each direction.

Anyways, yes, i see the effect. Cool.

The oncoming car is outside the shoulder. Pause the video on 0:15, and follow the line that separates the shoulder from the rest of the road.

 

[Costas Athan]

This is The Garage, not Digital and Video Cameras.

A topic doesn't strictly fit in one section... If there was a physics section then there would be a clear winner. In this case I thought this section was more appropriate.

 

[DominionSeraph]

A topic doesn't strictly fit in one section... If there was a physics section then there would be a clear winner.

Why the heck would you think this would belong in a physics forum? It's an arbitrary sampling of a physical phenomenon.
Do you think speeding up a video by 2x or running it backwards would belong in a physics forum?
Hey look, a sequence of still images! Physics!

 

[Costas Athan]

Why the heck would you think this would belong in a physics forum? It's an arbitrary sampling of a physical phenomenon.
Do you think speeding up a video by 2x or running it backwards would belong in a physics forum?
Hey look, a sequence of still images! Physics!

I don't think slowing down the video belongs to a physics forum. The stroboscopic effect is the one that belongs there and I uploaded the video to show the stroboscopic effect, not just that the video contains a slow motion part!

 

[DominionSeraph]

I don't think slowing down the video belongs to a physics forum. The stroboscopic effect is the one that belongs there

It in no way belongs there.
If I take a picture of my mouse, move the mouse around, move it back to the original position, and take another picture, the appearance of it being stationary in the two pictures isn't a physics phenomenon.
If I have two mice and I swap them out in between pictures, the appearance of one stationary mouse isn't a physics phenomenon.

This is only an optical illusion. As far as physics is concerned, you have 30 mundane frames per second.

You are way too impressed with this.
If you think the illusion of a stationary wheel belongs in a physics forum, then this must warrant a Nobel Prize:
http://www.youtube.com/watch?v=nzpChbJfrCY

 

[Meghan54]

I guess this one is right up there with your "OMG DRIVING THROUGH A MONSOON!" post which failed to deliver.

It was a drizzle.

This is that guy? That explains this thread.

I just wonder why the OP has such a fascination with things only a 3 year old would find interesting.

 

[Costas Athan]

It in no way belongs there.
If I take a picture of my mouse, move the mouse around, move it back to the original position, and take another picture, the appearance of it being stationary in the two pictures isn't a physics phenomenon.
If I have two mice and I swap them out in between pictures, the appearance of one stationary mouse isn't a physics phenomenon.

This is only an optical illusion. As far as physics is concerned, you have 30 mundane frames per second.

You are way too impressed with this.
If you think the illusion of a stationary wheel belongs in a physics forum, then this must warrant a Nobel Prize:
http://www.youtube.com/watch?v=nzpChbJfrCY

It's an optical phenomenon. They are studied by physics, impressive or not.

 

[Costas Athan]

This is that guy? That explains this thread.

I just wonder why the OP has such a fascination with things only a 3 year old would find interesting.

I don't know many 3 year old kids that are aware of Aliasing in the field of Signal processing. Do you? If you do, you have a point, otherwise you are talking nonsense.

 

[Railgun]

It is in Greece. There is a broken line so yes, it is legal. You can overtake a car using the opposite direction of the road if the line is broken. This applies worldwide! There is one lane, but the Cayenne moved kindly to the shoulder to make me some space. I touched the pavement markings in the middle of the road, only with my left wheels.

You were in the other lane while oncoming traffic was there. No, that does not apply worldwide. That's flat out stupid.

 

[Costas Athan]

You were in the other lane while oncoming traffic was there. No, that does not apply worldwide. That's flat out stupid.

You are wrong. I'm in the opposite lane by just only half a meter maximum. The 170 degrees field of view (I have set GOPRO to Wide) makes you misjudge distances. Also the mounting position of the camera (right side) contributes to it.

But lets assume that my entire car is in the opposite direction. Pause the video at 0:15. You can see that the car that's visible on the left is just outside the shoulder of the road. Both cars are about two meters wide. Can you explain me how two cars can fit in a single lane without making contact? And why the driver of the other car doesn't try to avoid me if I'm moving heads on?

The total width of the road is 11 meters. Subtract the width of the two emergency lanes ad calculate the width of each lane.

 

[soccerballtux]

I don't know many 3 year old kids that are aware of Aliasing in the field of Signal processing. Do you? If you do, you have a point, otherwise you are talking nonsense.

actually I asked about this effect when I saw it on TV when I was 7 or 8 and had it explained to me. I understood it from that point forwad.

That said I see no reason for all this hate....