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Golf Shaft Flex Distortion



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I see a lot of videos and photos posted with radical shaft bend.
The problem is, that bend is not real. Modern digital cameras use a cheap CMOS sensor to read the image. These cheap sensors mimic a rolling shutter by reading an image a line at a time. CCD sensors read the whole image at once (global shutter), but are usually limited to 30fps because of cost. High speed cameras with global shutters cost a lot of money. So, if your high speed camera cost you less than $10k, it most likely has a sensor that mimics a rolling shutter.

I used white athletic tape on the dark colored shafts. I always keep two rolls in my bag. 🙂

If you want to look into an in depth study of shaft flex and kick then I recommend this site:
http://www.tutelman.com/golf/shafts/ShaftLab3.php#bigbendtoeup

Casio cameras also have a rolling shutter and skew the shafts.
See these videos for proof:


Script for language translation:
0:03 – This video was shot with a very inexpensive camera; VGA quality, 18 frames per second. Note how bad the distortion is when the club gets to the bottom of the screen. Even waggling the club causes the shaft to skew forward.
0:25 – When we turn the camera sideways, with the top of the camera pointed down range, we get a much straighter look at the shaft when it gets near the ball. However, when it gets to waist level, it is still skewed.
0:48 – Now let’s take a look as some stills. Here with the camera upright you can see alot of skew. When I turn the camera sideways and rotate the view, the shaft looks very straight. Again upright, a lot of skew, not correct. Camera sideways, just a touch of bend, this is the correct look.
1:10 – Camera upright, shaft at waist level, the shaft is correct but the club head is stretched. With the camera turned, you see a lot of skew.
1:22 – Pre-impact, a lot of forward skew. With the camera turned, you can see the shaft droop, which is the correct look, but the club head has been squished.
1:32 – Post-impact, a lot of forward skew. With the camera turned, the shaft is bent backward, this is the correct look. But again, the club head is squished.
1:47 – Note the location of the hands in each of these stills. As I get closer to the camera, the skew grows. And in the last still, the skew is extreme.
1:58 – Post-impact, from a distance the shaft doesn’t look to bad, there is some skew. But, as we get closer, the skew becomes greater and you can see the shock wave that’s in the shaft that gives it that snake like bend.
2:14 – I shot this video with the Sanyo XACTI FH1a. It shoots slow motion video. I used the 240 frames per second setting with the ISO set at 800.
2:29 – From a distance, no skew can be seen. But as we get closer, the skew becomes very obvious.
2:39 – I tested the Sanyo XACTI with 7 different golf shafts. I wanted to compare the amount of forward skew with the upright camera position, with the amount of skew that’s shown when the camera’s top is pointed down range. I took a full hard swing with every single club regardless of flex. My swing speed averages around 102 MPH (164Km/Hour). I saw very little difference in the amount of forward flex in the videos at either angle. The ladies flex clubs where very difficult to hit with a full swing.
3:16 – This is droop. This image appears to have no distortion, you can tell this because the ball mostly round. Droop will appear in the video if the camera is set up down range of the golfer and looking back at an angle. If the camera is set behind the golfer and looking forward at an angle, the droop will be completely hidden.
3:43 – Jamie Sadlowski, shown in magazine shots with a lot of skew in his shafts. Note when he’s shown on the “Konica Minolta Swing Vision” his shafts are very straight. (3:56)Same tournament, same day, amatuer camera versus Swing Vision camera.
4:02 – This hangs in the fitting booth at the local golf store. You go in for a fitting, they’ll point to the pro (professional), show how his shaft is bending forward and tell you how important your flex is. But that pro’s shaft is not really bending like that.
4:19 – So if you have a consumer type camera and you still want to be able to shoot you videos. I recommend that you turn the camera sideways and point the top of it down range, and just go ahead and shoot the videos. Take the camera home, put the videos on your computer and rotate them back upright using a video editor. And watch them that way. It’ll show you all your body positions which is the most important thing you’re looking for. The shaft will be skewed but that’s no big deal.
Thanks so much for watching, I hope you found this video useful.

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21 responses to “Golf Shaft Flex Distortion”

  1. Thanks for this. I was looking at a slow mo instruction video today and stopped it at the impact frame. Lots of forward shaft flex and shows the loft of the club increased. Just the opposite of the hands forward impact position everyone is pushing. So I wondered if the hands forward position was therefore some way of compensating for this forward shaft flex. Then wondered about camera distortion and found your excellent video. Thanks again!

  2. Andy B says:

    I think he is just swinging so fast that the shaft is bending backwards.

  3. adritch says:

    How does this apply to today's tech? Are better sensors now cheaper. Just curious as this was from 5 years ago, and a lot can change. Thanks.

  4. Thank you for this. I just filmed 4 different drivers I was testing. Using my Gopro I was shocked when I saw the shaft distortion and thought maybe I was slowing my hands or something similar to that. Whew, crisis averted.

  5. Dylan Holt says:

    Thank you so much for making this video. I have been going crazy with this problem for years thinking I'm doing something wrong in my swing that makes the shaft kick way early. I had a hard time believing that the shaft was that bent before impact. I'm surprised this topic isn't discussed more in the golf world as I'm sure anyone with a standard camera filming their swing is dealing with the same issue

  6. mo747747 says:

    Awesome video. There is no way a club can be forward with the shaft so far back, skewed a foot back. Your video makes so much more science sense.( And my club fitting guys are super too!)

  7. John T says:

    I can buy your argument that the shaft does not bow backward like you show for less expensive cameras.  But wouldn't it be bowing forward somewhat before impact, instead of being straight?   With all the clubhead speed I would think you have a forward bowing shaft.  You can easily bend a regular flex shaft so I think centrifugal force could easily bend it?

  8. Interesting video.  I'm going to send this to my lead club fitter.

  9. g scribling says:

    Rolling shutter problem.

  10. John Fagley says:

    Excellent video.  Clear explanations.  I like the idea of rotating camera 90 degrees for most accurate representation of shaft angle at impact.  Thinking about getting Kodak Zi12 for $150, mostly for seeing body positions.  Can you recommend any better options in same price range?

  11. Totally true. funny thing is the inconsistency of people who believe this is actual flex. Why would we be fitting clubs to exact loft angles (in case of tour pro's up to 0.1*) if the club flexes variably 20-50* at impact? Of course not. Try and bend a shaft for 30*, that is really hard to do, if you don't crack it.

    Is there any way to identify which chips or camera's don't have this problem?

  12. bogushavis says:

    You are correct. If the camera is upside down, the shaft bends backward. There is a golf blogger who has done this with his videos. He claims he gets less distortion this way, but I'm pretty sure he just does it to mess with people.
    I would have done it in this video, but I can't get my tripod to hold the camera completely upside down. I couldn't get any "volunteers" (my kids) to hold the camera for me that day.

  13. geoff2010s says:

    Thanks. This explanation seems correct.
    It would be interesting if you tried this with the camera upside down. Based on your explanation, one would expect the shaft to be bent the other way if the video were to be taken with the camera upside down.

  14. Jimmy Chia says:

    awesome..thanks for clearing the air

  15. bogushavis says:

    A Bizhub is a printer not a camera. Check out the Phantom camera. /watch?v=DLBzp1wBB2k
    Forward bend is caused by centripetal force on a wood type clubhead. The amount of bend depends on flex, the offset of the head's C.O.G., and head speed. It has very little to do with a "good golfer". Anyone who can swing a club will get a tiny amount of forward bend.
    This video is not about that. It's about not using your camera to analyze your shaft flex, cameras are useless for this task.

  16. Im sorry sir but your concept here is a bit distorted. The shaft does bend forward past halfway on the downswing with a good golfer. The new high speed cameras like bizhub point this out when looking at the swings of tour players. it is certainly not as much as it is happening in the videos you are showing, but it does happen The reason this happens with a good player is because the downward force of the clubhead is greater than that of the grip so the shaft bends forward toward the ground

  17. bogushavis says:

    This is just the type of comment I love to see!
    I saw a post where a guy kept changing his iron shafts and was now using Project X 7.0's. He was unhappy because they were still bending in the video.
    Another guy kept going back to the shop to have his driver reshafted until he had the heaviest, stiffest shaft they sold.
    That's a lot of expense and time for a bad return. I hate the feel of a shaft that is too stiff. It makes my wrist hurt just thinking about it.

    Thanks for commenting!

  18. uh….I just called a friend of mine today about getting a new shaft due the video that I took with my shaft all distorted…this really clears everything up.

    thanks

  19. bogushavis says:

    …cont'd:
    You need minimum of 60FPS if you want to "analyze" a swing. 240FPS or higher looks best when played back "slow motion" at 30FPS.
    To get a true picture of the shaft you need a high speed camera with a global shutter. Phantom cameras use a CMOS with a true global shutter. They cost over $100k. Look at this vid, it was shot with a Phantom. /watch?v=DLBzp1wBB2k
    The channel it's on has a bunch of Phantom video, it's all good stuff, give it a look.
    Thanks for commenting!

  20. bogushavis says:

    Neither.
    The bend is caused by the type of electronic shutter. Most consumer cameras use a CMOS with an electronic "rolling shutter". No matter how you set the ISO, shutter speed or FPS, the electronics read in the image one line of pixels at a time.
    Some high end consumer cameras use a CCD sensor which always has a "global shutter". Global shutters read the entire frame simultaneously. However, global shutters require a lot faster data throughput so these cameras are limited to 30FPS.
    cont'd…

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