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Old 07-26-2012, 06:14 AM   #15
Chas Tennis
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Join Date: Feb 2011
Location: Baltimore, MD
Posts: 3,260
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Quote:
Originally Posted by jaykay View Post
Chas - Can you upload some videos from your Aiptek at 720p 60fps?
Sample videos of a backhand and forehand using the AIPTEK ActionHD (5 Megapixel) camera in 720 60p mode.

Forehand
https://vimeo.com/46427326

Backhand
https://vimeo.com/46427230

These videos display considerably more sharply directly on my computer and not through Vimeo. Compression issue? These were taken in bright sunlight. Notice that the edges of the racket and other rapidly moving edges do not have excessive motion blur.

Jello Effect Distortion. On the backhand video, stop frame right after the ball impact. You will notice that the racket face appears to be bent. I believe that is false image bending due to Jello Effect distortion of the AIPTEK under these specific shooting conditions.

How is this camera any better than a smartphone cameras or any other 60 fps progressive camcorder or camera? Smartphone cameras also seem to select a very fast shutter speed in bright sunlight. Test motion blur. Is the smartphone 30 fps or 60 fps? Smartphones have a fixed wide angle lens and not a 3X Zoom like this Aiptek and therefore require closer positioning of the camera for acceptable image size. There is more distortion using wide-angle fixed lens. How much Jello Effect is there on a given model of smartphone? Other 60p camcorders/cameras have an unknown amount of Jello Effect. Most importantly it is unknown how the AUTO exposure control will select shutter speed. Test any video camera or smartphone in bright sunlight to observe motion blur.

I hope that there are some properly framed Smartphone, GoPro Hero 2, and other 60p videos for comparisons of tennis stroke videos.

Outdoor sunlight lighting is about 100X as strong as indoor lighting so AUTO will have to select a much slower shutter speed with much increased motion blur.

Unfortunately, this Aiptek model is an older one and I don't know how other Aiptek models perform. I have found it impossible to find information on how the AUTO exposure control works in any camera models from any manufacturer. Suggest testing the cameras for motion blur in bright sunlight.

Last edited by Chas Tennis : 07-26-2012 at 06:49 AM.
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