Camera to film tennis

Discussion in 'Tennis Tips/Instruction' started by TRVX1912, Feb 18, 2013.

  1. TRVX1912

    TRVX1912 New User

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    Looking for a reasonable price camera to film my tennis any thoughts
     
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  2. Chas Tennis

    Chas Tennis Hall of Fame

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    Ask yourself whether you want mostly to
    1) video your matches or
    2) take high speed video of your tennis strokes

    http://tt.tennis-warehouse.com/showthread.php?t=431983

    http://tt.tennis-warehouse.com/showthread.php?t=405536

    Search also Kinovea and dpreview.

    High Speed Video for Stroke Analysis. The highest quality for high speed video of strokes are used or left over new stock Casio cameras - models F1 (2008 ), FH20, FH25, FH100(2010). Check costs which have steeply risen for used and left over new stock. My FH100 is excellent for HSV and also does HD video. Unfortunately, I don't know of any current cameras now offered with manual exposure control in high speed video mode.

    FH100 sample HSV usually at 240 fps and 1/10,000 sec exposure.
    https://vimeo.com/user6237669/videos

    Greg G just found that an older Casio FC150 can also do very fast shutter speeds, see later replies in the above links and his forehand thread. Maybe you can find a used one at a reasonable price as he did.

    There are many other HSV cameras that might have fast shutters and take videos with small motion blur but learning what might be out there is not easy. Also, cameras have flaws such as short recording time or poor single frame viewing or editing on the camera itself.

    See misc camera models discussed toward the end of the large Casio Camera Thread
    http://www.golfwrx.com/forums/topic/250245-casio-camera-thread/page__st__750

    Maybe the $130 Canon PowerShot ELPH 100 HS reply #755 of the above link is a useful camera at a very low price. ???
    http://www.youtube.com/watch?feature=player_embedded&v=31ypqx5pbsE See reply #8 for the Canon Powershot video. I don't know much about this camera.

    For just viewing your match I like the old Aiptek Action camera but only the specific model mentioned in the above threads. It has a fast shutter in direct sunlight and does 60 fps. The fast shutter is a very important feature but when you find a camera model that does HSV you will likely have difficulty determining whether the shutter is fast for AUTO exposure control cameras.
     
    Last edited: Feb 19, 2013
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  3. TRVX1912

    TRVX1912 New User

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    Have you ever used the kodak playsport?
     
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  4. Chas Tennis

    Chas Tennis Hall of Fame

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    I have not used the Kodak Playsport. What's the frame rate?

    The main question for cameras that do high speed video is how fast is the shutter speed? A fast shutter speed reduces motion blur of the faster things such as the racket and the tennis ball.

    Since almost all cameras in high speed video mode use AUTO exposure control and it is very difficult to find information on shutter speed, I look for Youtube videos to display motion blur. An ideal subject is a golf swing in bright direct sunlight when viewed from the side so that the club head is going across the frame. Search: (camera model) + golf + Youtube + ? high speed video etc.

    Golf swing in direct sunlight side view
    http://www.youtube.com/watch?v=fwPpScgNstw

    (The forward and backward arrows work to advance on go back a single frame.)

    Around 16 the club travels maybe 2 feet between frames so it does not appear that the frame rate of this particular video clip is very high, maybe only 60 fps. Not HSV.

    At 16 you can see the club head contacting the ball. The motion blur does not look too bad and also the club head might have a velocity of about 100MPH. Shutter speed maybe around 1/2000 sec? Needs a closer view of the club head to actually measure motion blur.

    That video is higher resolution than most high speed video cameras. The video also displays Jello Effect distortion by the false bending of the club shaft. The Jello Effect does not look too bad but it should be kept in mind when looking for accuracy in very fast tennis motions.

    Features that are important
    1) Can you view stop action on the camera?
    2) Does it only have a wide angle lens?
    3) How does the AUTO control shutter speed work in less light than direct sunlight? [The light level of direct sunlight is roughly 100X that of indoor tennis courts -low indoor lighting levels require slow shutter speeds for all HSV cameras.]
     
    Last edited: Feb 19, 2013
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  5. TomT

    TomT Hall of Fame

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    Have you checked out gopro yet?
    http://gopro.com/
    It's impossible to know what you mean by reasonable. The gopros aren't super cheap but they're not unreasonably expensive considering the quality, imo.
     
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  6. TRVX1912

    TRVX1912 New User

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    the go pro the fish eye is annoying. Also the kodak play sport is 60fps 720p
     
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  7. TRVX1912

    TRVX1912 New User

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    And Why have the casio camera risen in price? isnt it suppose to go down lol
     
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  8. Torres

    Torres Banned

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    Great info Chas.
     
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  9. Chas Tennis

    Chas Tennis Hall of Fame

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    A very fast shutter speed is necessary for small motion blur. Manual exposure control to set the shutter speed is the best for high speed video. Plus other high performance features such as LCD viewing, editing, etc. for high speed video analysis. Buyers with high speed video applications who understand these issues drive up the Casio prices.
     
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  10. sureshs

    sureshs Bionic Poster

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    Contact John Yandell at tennisplayer.net - he is the authority on high-speed video for tennis
     
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  11. aimr75

    aimr75 Hall of Fame

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    Chas, the pana lumix fz200 does some good high speed video in HD. I shot this at this years AO:

    http://youtu.be/-e1gmXf7h54

    Just select the HD option on YouTube
     
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  12. TRVX1912

    TRVX1912 New User

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    That looks sweet I might go with this one though Canon PowerShot SX50
     
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  13. zapvor

    zapvor Legend

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    i just use the camera on my phone. you can see the quality on youtube. not bad
     
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  14. Chas Tennis

    Chas Tennis Hall of Fame

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    That is very nice.

    Shutter Speed Estimate from Motion Blur. To get an idea of the shutter speed, use the ball diameter for a scale. The ball diameter is spec'ed to be 2.6 inches. There is motion blur mostly in the travel direction but not in the direction perpendicular to the ball's trajectory.

    Measure the ball height by placing a piece of paper on the screen and making marks on the paper with a pencil. Measure the ball length with motion blur along the trajectory. I get that the blurred ball is about 1.5 times as long as it is high. With motion blur of the front and back edges it appears 3.9 inches long. The front and back edge each have 0.7" of motion blur.

    For a point on an object moving directly across the frame.

    Motion Blur = Ball Velocity X Exposure Time

    Ball velocity is unknown but can be estimated. Estimate ball velocity at 50 MPH.

    Conversion:
    100 MPH = 1760"/sec
    50 MPH = 880 " / sec

    For a 50 MPH ball
    0.7" = 880"/sec X Exposure time
    Exposure time = 0.7"/ 880"/sec
    Exposure Time = 0.0008 sec or about 1/1000 sec.

    That is, if the ball had a velocity of 50 MPH the shutter speed in direct sunlight would be about 1/1000 sec. The camera's AUTO exposure control selected a shutter speed of about 1/1000 sec.

    The ball velocity could also be measured fairly accurately, but there is an error because the trajectory is not quite perpendicular to the viewing angle of the camera.

    (BTW, if you type in "X MPH to ft/sec" in the Google Search box it converts right under the box)
     
    Last edited: Feb 21, 2013
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  15. TRVX1912

    TRVX1912 New User

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    Hey Chase What do you think of the Canon powershot sx 50hs?
     
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  16. Chas Tennis

    Chas Tennis Hall of Fame

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    Last edited: Feb 20, 2013
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  17. dominikk1985

    dominikk1985 Legend

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    you Need at least 30 FPS, better 60+.
     
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  18. Tight Lines

    Tight Lines Semi-Pro

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    Why not just use an Iphone 4s or better with a SloPro app (free app to record and view, but need premium to export the video out $3.99) that allows you to record at 60 fps? Cheapest option you already have the phone.

    Harry
     
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