Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
Would anyone like to try to explain how this effect occurs?
I'm assuming it is because, unlike still photos of stage coach wheels turning backwards, the recording camera scans down the subject, so movement makes a slightly different scene appear in each succeeding scan line.
I've noticed that on TV commercials for cars, as sophisticated as our technology has become for manipulating digital images, we still can't (or don't) make car wheels look like they are turning in the right direction.
Location: The Raider Nation._ Our band kicks brass
1,853 posts, read 9,690,453 times
Reputation: 2341
Most likely manipulated.
It helps to know what you are looking at. The propeller tips have the white stripes. The roots are black. The video makes it appear that they are passing right through the hub.
I first thought that we were looking at another engine, but that is the right inboard engine. I can't say how they did it, but I don't think that is a natural occurance.
Edit: I watched it a few more times. Facing forward the propeller is turning in a clockwise direction. Look at the hub, you can see the prop coming towards you from the bottom. At about the 7:00 position, you can see two props blended together. There are white tips on both ends. It could be the slow shutter speed on the camera blending the two together. That is most likely a 5, or 6 bladed prop. So I'm leaning towards a natural affect from the camera.
I know that I would never convict anybody on just pictures anymore. They had better have some other hardcore evidence
Last edited by South Range Family; 08-31-2010 at 06:33 PM..
Would anyone like to try to explain how this effect occurs?
I'm assuming it is because, unlike still photos of stage coach wheels turning backwards, the recording camera scans down the subject, so movement makes a slightly different scene appear in each succeeding scan line.
I've noticed that on TV commercials for cars, as sophisticated as our technology has become for manipulating digital images, we still can't (or don't) make car wheels look like they are turning in the right direction.
That's mainly due to the sampling rate of any video recording device being very slow relative to the motion. Even if it's fake (which could be true since it's not blurry at all), most video is around 30 frames a second, but in order to catch the real motion you would need over twice the rate of the motion in action. So if the wheels spin at 100 rotations a second, you would need at least 200 frames a second to catch it correctly. There are various high speed motion capture cameras available, but at significantly greater cost than normal devices.
Frame rate combined with scan rate within frame, data is transferred from the CCD to memory as serial data.
In other words, if I may translate, the entire image is not simultaneously being captured true-form, as it would be in a mechanical shutter open-close cycle. Different lines of the image are being captured at different times, with the prop blade in a new location with each scan. So each line of the scan shows that line of the prop image in a new place, that doesn't match up with its old location in the previous scan.
Please register to post and access all features of our very popular forum. It is free and quick. Over $68,000 in prizes has already been given out to active posters on our forum. Additional giveaways are planned.
Detailed information about all U.S. cities, counties, and zip codes on our site: City-data.com.
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
