Video Camera for Slow-Mo Swing Analysis - AVS Forum
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post #1 of 28 Old 11-18-2012, 10:05 PM - Thread Starter
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HI

I'm looking to buy a video camera that is able to capture my baseball swing so that I can analyze different components of my swing. I've done quite a bit of research and initially I heard that 60fps at 720p should do the trick, however now I'm hearing that at 60fps I might get significant blur with the bat. What I want is a camera that will give me high quality slow-motion video without any lagging or blur. I would like to be able to use Twixtor and slow it down even further later. I don't really want to spend over $300. After some research I was thinking about getting the Go Pro Hero 3, White Edition which runs for $200 and has 1080p 30fps, 720p 60fps and is small and durable. However now I'm thinking I might need a camera that shoots at a higher fps rate.


Here is kind of what I'm trying to do, without the smoke and multiple camera angles. Basically I'm trying to get a slow-motion video at a high quality that I can use Twixtor on without the bat blurring.

http://vimeo.com/25037488

Thanks,

Jordan
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post #2 of 28 Old 11-19-2012, 02:48 AM
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Blurring has nothing to do with frame rate. Whether the bat is blurred depends on shutter speed, which can be set to any value, regardless of frame rate - if you want no blur, you use a high shutter speed. The frame rate determines how fine you can break down the swing (how many segments per swing).

So, how many frames per second do you need to analyze a bat swing - 60fps, slowed down? 120fps, slowed down?

The Sony Action Cam does 720 at 120fps.
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post #3 of 28 Old 11-19-2012, 08:54 AM
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Quote:
Originally Posted by markr041 View Post

Blurring has nothing to do with frame rate. Whether the bat is blurred depends on shutter speed, which can be set to any value, regardless of frame rate - if you want no blur, you use a high shutter speed. The frame rate determines how fine you can break down the swing (how many segments per swing).
So, how many frames per second do you need to analyze a bat swing - 60fps, slowed down? 120fps, slowed down?
The Sony Action Cam does 720 at 120fps.

I wish I knew what cameras are available, >60 fps, that can set shutter speed in high speed video mode. I don't know of any currently offered but I'd like to find any that are. It is difficult to determine reading most specs whether the camera is capable of setting set shutter speed in HSV mode. Downloading the full manual and going through it carefully is better but impractical with the many camera models. I believe that there are several available models, DSLR's, that will allow setting shutter speed at 60 fps.

Do you have the SONY Action Cam? It sets shutter speed? What is the fastest shutter speed?

The Casio cameras models F1(2008), FH20, FH25, and last the FH100(2010) had excellent excellent capabilities for sports analysis and were affordable. They are available used or left over new stock but are more than $300.

It is a good idea to find high speed videos on Youtube or Vimeo to confirm that the camera is capable of small motion blur. A golf club swing viewed from the side where the club head is moving 100 MPH across the frame is very good for seeing motion blur. The behind view is not good as the club head is moving away from the camera. Only look at ones in direct sunlight - where very fast shutters are possible - as indicated by obvious sharp shadows in the videos. Search - Camera model + high speed video (or frame rate, 120 fps) + golf, etc. There is no way to tell whether the camera was operated to minimize motion blur. Some cameras in AUTO modes may select faster shutters speed.

Some more discussion on high speed video cameras. http://www.kinovea.org/en/forum/viewtopic.php?id=435

After you get the camera Kinovea is free video analysis software that allows comparisons, side-by-side, of two videos, batters, etc. Kinovea has many other analysis capabilities.
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post #4 of 28 Old 11-19-2012, 10:19 AM - Thread Starter
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Thanks for the help. I think 60fps slowed down should do the trick. It looks like I'll be reading a lot of manuals regarding shutter speed. Thanks again.
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post #5 of 28 Old 11-19-2012, 10:58 AM
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Quote:
Originally Posted by JMcComb7 View Post

Thanks for the help. I think 60fps slowed down should do the trick. It looks like I'll be reading a lot of manuals regarding shutter speed. Thanks again.

I don't know the speed or motions within a bat swing. For tennis there is a lot of very rapid arm & hand rotations similar to the very rapid baseball pitching motion (which is even a little faster I think). For those rapid motions 60 fps is not enough. Also, 60 fps will not catch the ball close to impact as often as you might like. What accounts for the ball's trajectory, the bat swing direction or how far above or below on the ball the impact point is? To determine how far the bat moves between frames see the frame rate discussion in the Kinovea thread above and use estimated bat swing velocity.

For analysis of tennis strokes I do mostly stop-action single frame and much less viewing in slowed motion. Remember also that if software creates false frames between recorded frames, the false frame could obscure something real that is very fast. That would happen on the tennis serve, for example. Most of the problems that I see on my tennis strokes are obvious errors that do not need high speed so any video would do and 60 fps would be very useful. For producing entertaining videos at 30 fps playing speed, to show swings for better viewing, the false frames probably do an excellent job.
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post #6 of 28 Old 11-19-2012, 11:55 AM
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There is a bridge camera - panasonic fz200 with high speed capability
120 fs at 720p or 240 fp and VGA
http://www.amazon.com/gp/product/B008MB6ZX0/ref=ox_sc_act_title_1?ie=UTF8&smid=ATVPDKIKX0DER

Honestly - I don't think this would be enough, but this is highly unlikely you find anything faster in consumer rate cameras.
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post #7 of 28 Old 11-19-2012, 12:40 PM - Thread Starter
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Quote:
Originally Posted by Chas Tennis View Post

I don't know the speed or motions within a bat swing. For tennis there is a lot of very rapid arm & hand rotations similar to the very rapid baseball pitching motion (which is even a little faster I think). For those rapid motions 60 fps is not enough. Also, 60 fps will not catch the ball close to impact as often as you might like. What accounts for the ball's trajectory, the bat swing direction or how far above or below the on the ball the impact point is? To determine how far the bat moves between frames see the frame rate discussion in the Kinovea thread above and use estimated bat swing velocity
For analysis of tennis strokes I do mostly stop-action single frame and much less viewing in slowed motion. Remember also that if software creates false frames between recorded frames, the false frame could obscure something real that is very fast. That would happen on the tennis serve, for example. Most of the problems that I see on my tennis strokes are obvious errors that do not need high speed so any video would do and 60 fps would be very useful. For producing entertaining videos at 30 fps playing speed, to show swings for better viewing, the false frames probably do an excellent job.

Thanks, that was very informative. The bad speed is roughly 85-90mph. My primary use will be stop-action analysis where I would be looking at different parts of my swing and measuring angles etc. However I would like to use effects such a Twixtor to do slow motion video more for entertainment, however if that's not possible I'm willing to give that up. I'm looking at the Sony Action Cam aprox. $200) which shoots 120fps at 720p it says it has shutter speeds of up to 10, 000 however it is more of a helmet cam style of camera like a go pro so I'm not sure how easy that will be to change shutter speeds manually. Another option I was looking at was the Casio Exilim EX-ZR100 ($250-$300) which shoots (1920x1080) 30fps, (640x480 30fps), (224x64 1000fps), (224x160 480fps), (432x320 240fps). And from what I've read you can manually set shutter speeds up to 1/40000 second.
Basically the Casio is a higher end camera that has many more features (also costs quite a bit more), but the Sony has a better picture (720p) at 120fps and for a very reasonable price. Are there any cameras that you know of that would be a good option at a similar price range. And which camera would you choose between the Sony and the Casio?

Thanks
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post #8 of 28 Old 11-19-2012, 02:01 PM
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The Casio ZR cameras 100, 200, 300 and probably the new ZR 1000 (?)cannot set shutter speed in high speed video mode -much to the disappointment of golfers. You can find that information on the internet and, I believe, in the Casio user's manual for each model in Notes for some models.

The Sony I believe has a very wide angle lens which distorts. The Sony as well as all these CMOS cameras have some degree of Jello Effect distortion that will distort the image. The more lines of resolution the larger the JE distortion since it is caused by a slight delay between the time each sensor line is read out. JE distortion is for you to determine if you want to do accurate analysis. The Casio FH100 has small JE distortion. See Kinovea forum thread on cameras for JE discussion.

Find some YT videos for each camera that you are interested in. If you can't find videos with small motion blur & JE distortion then you can't be sure the camera is capable of high speed video with sharp & accurate images. Remember though that often the camera was not operated optimally to minimize motion blur.
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post #9 of 28 Old 11-20-2012, 07:08 PM
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Another interesting camera for this could be the new GoPro Hero3 Black Edition. It does 1440p-48, 1080p-60, 960p-100, 720p-120 and WVGA-240 !!!

If you have a simple tripod and the 1/4-20 mount it could be a perfect tool to watch via wireless to your smart phone right there on the spot.

I have a Panasonic TM700 that does pretty awesome 1080-60p, but it's nothing like the video you showed above. Definitely need some higher frame rates to get what your looking for there.

Cheers,
Pete
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post #10 of 28 Old 11-20-2012, 09:05 PM - Thread Starter
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Ok, after quite a bit of research I have found it very difficult to find a high speed camera that has manual shutter speeds without spending at least $500. If anyone knows of any please let me know. I know many cameras have a sports mode where the shutter speed would be increased however you wouldn't have full control. I still think the Sony Action Cam is a very good option, has anybody used one before? And I've been unable to see a golf or baseball swing on youtube using it. I would like to see how it functions.
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post #11 of 28 Old 11-23-2012, 07:56 PM
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My old sony hdv hc3 high def actually has mode knon as"golf mode". Takes a of frames for 15 secs so, plays them back slowly.The only real use is for analyzing
your golf swing.
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post #12 of 28 Old 11-24-2012, 02:55 PM - Thread Starter
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I've been able to find a couple Nikon V1 10.1 Megapixel Mirrorless Camera for under $400 used or refurbished. It shoots
HD: 1920 x 1080/60i
HD: 1920 x 1080/30p
HD: 1280 x 720/60p
Slow-motion: 640 x 240/400fps
Slow-motion: 320 x 120/1200fps
Has anyone used this camera before. I would love a review, it seems like this could be a pretty good option if I could get it for under $400
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post #13 of 28 Old 11-24-2012, 03:29 PM
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The GoPro controls exposure via shutter, so actually in good light it will go to exactly the kind of short shutter speeds you need. Manual won't really be necessary; can probably just set it to 720p/120 and enjoy. Even at a 360 degree shutter it'll probably be very good.
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post #14 of 28 Old 11-24-2012, 06:00 PM
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Quote:
Originally Posted by JMcComb7 View Post

I've been able to find a couple Nikon V1 10.1 Megapixel Mirrorless Camera for under $400 used or refurbished. It shoots
HD: 1920 x 1080/60i
HD: 1920 x 1080/30p
HD: 1280 x 720/60p
Slow-motion: 640 x 240/400fps
Slow-motion: 320 x 120/1200fps
Has anyone used this camera before. I would love a review, it seems like this could be a pretty good option if I could get it for under $400

Check the specs with the user's manual or elsewhere but I believe that the Nikon V1 and J1 cameras are severely limited in recording time in high speed video mode. 5 seconds? If true that short a recording time is a show-stopper for my application.

http://forums.dpreview.com/forums/post/39424744
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post #15 of 28 Old 12-04-2012, 11:01 PM - Thread Starter
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Thanks for the help once again. I've been searching for a long time now trying to decide what my best option is. I've decided that for what I would really want (high fps, manual shutter speed) I am going to be well over my budget. I've narrowed to down to a couple cameras. I'm thinking either the Sony Action Cam or the Canon Elph 100HS which can surprisingly shoot good video for a cheap camera. http://www.usa.canon.com/cusa/consumer/products/cameras/digital_cameras/powershot_elph_100_hs?color=Gray#Specifications
If anyone has used either or has another camera that is fairly cheap, I would love to hear your opinion.

Thanks
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post #16 of 28 Old 01-25-2013, 06:53 PM
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just wondering if you ever came up with a solution? i'm in the same boat for the upcoming baseball season. Granted it is for a youth baseball team but nonetheless still like to get something for pitching and swing mechanics. I checked out all the above mentions as well as the jvc gx250 which says it shoots at 300fps. i'm new to all this so I am not quite up to speed on shutter speed and things like that.

any new info on this?
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post #17 of 28 Old 01-26-2013, 11:09 AM
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For a related topic (http://www.avsforum.com/t/1454343/jvc-ex250 I decided to see what I could do with ordinary equipment. I pulled a 1080p60 clip from last year shot with a common 1080p60 camera. I ran it through the slow motion tool of my favorite editing software and got this: https://vimeo.com/58252577. To see what would happen, I did it again and got it even slower: https://vimeo.com/58254299. Even though now grainy from all the processing, you can still see the muscles in her upper arm after she misses the ball.

These two clips are not going to win awards or match the OP's clip of Carlos Serrao. The bat and ball blur, but, if the goal is to analyze body motion, I think it works.
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post #18 of 28 Old 01-26-2013, 11:31 AM
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Quote:
Originally Posted by bsprague View Post

For a related topic (http://www.avsforum.com/t/1454343/jvc-ex250 I decided to see what I could do with ordinary equipment. I pulled a 1080p60 clip from last year shot with a common 1080p60 camera. I ran it through the slow motion tool of my favorite editing software and got this: https://vimeo.com/58252577. To see what would happen, I did it again and got it even slower: https://vimeo.com/58254299. Even though now grainy from all the processing, you can still see the muscles in her upper arm after she misses the ball.

These two clips are not going to win awards or match the OP's clip of Carlos Serrao. The bat and ball blur, but, if the goal is to analyze body motion, I think it works.

This type of post processing for playback cannot add information to the original video. The processing duplicates frames or fabricates false frames that cannot be used for accurate analysis. It has a very useful role for entertainment only. For analysis you would be less likely to be mislead by examining the original video at 60 fps.

A high speed video of a tennis serve. 240 fps and 1/10,000 shutter speed for small motion blur.
https://vimeo.com/27528701

Watch the elbow bones turn rapidly. That upper arm rotation (internal shoulder rotation) contributes the most to racket head speed at impact. At 240 fps the video shows 7 frames. The twitch-like rotation lasts about 0.03 second. At 30 fps (0.033 sec between frames) you might catch the rotation in one frame or maybe none. At 60 fps (0.017 sec between frames) you should get it in just one frame.
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post #19 of 28 Old 01-26-2013, 12:34 PM
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Quote:
Originally Posted by Chas Tennis View Post

This type of post processing for playback cannot add information to the original video.
Of course it can't. Everybody is smart enough to figure that out.

But, showing people how to use common video equipment and software may be useful. Posting what I did should demonstrate to sports perfectionists both the limitations and opportunities of everyday equipment. The FH100 you used in the tennis shot may be hard to find and expensive. On a quick search, I found one for $900. The common Sony I used for the softball shot was $300.

It would be up to the batter to see what value is in a 60p clip slowed down. He/she might learn more equipment is necessary.

But for a family guy with a family camera try to coach or help coach a kids' team, some 60p might be good enough.

Someday my wife will let me touch her FZ150 camera and I will get a chance to compare the low res 240fps to the higher res 60fps pointed at a softball player in the family.

Bill
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post #20 of 28 Old 01-26-2013, 01:00 PM
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Quote:
Originally Posted by bsprague View Post

.............. Everybody is smart enough to figure that out. Some new people may not make that distinction, or ever buy high speed video cameras, who knows?
....................................................................................................................................................
But for a family guy with a family camera try to coach or help coach a kids' team, some 60p might be good enough. 60p with a very fast shutter is very useful. See Kinovea forum discussion on frame rates.

Someday my wife will let me touch her camera and I will get a chance to compare the low res 240fps to the higher res 60fps pointed at a softball player in the family. I doubt it. You seem addicted to high spatial resolution & post processing and will probably never touch high temporal resolution....real high speed video. Post a single high speed video, Bill, .....just one...........

Bill
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post #21 of 28 Old 01-26-2013, 06:04 PM
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if i could find a fh100 i would be all over it! it's like trying to find bigfoot!!! hahaha
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post #22 of 28 Old 01-26-2013, 07:36 PM
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can some explain what the following means?

[High Speed Video] 1280 x 720 pixels, 30 fps (MP4) (Sensor Output is 120fps) / 640 x 480 pixels, 30 fps (MP4) (Sensor Output is 240fps)

does this mean it records at 30fps and upconverts??? i'm totally lost here

edit--- got my answer... Thanks Chas!
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post #23 of 28 Old 01-27-2013, 08:33 AM
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Quote:
Originally Posted by djmas View Post

can some explain what the following means?

[High Speed Video] 1280 x 720 pixels, 30 fps (MP4) (Sensor Output is 120fps) / 640 x 480 pixels, 30 fps (MP4) (Sensor Output is 240fps)

does this mean it records at 30fps and upconverts??? i'm totally lost here

edit--- got my answer... Thanks Chas!

What camera are you writing about?
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post #24 of 28 Old 01-27-2013, 08:53 AM
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panasonic fz200
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post #25 of 28 Old 01-27-2013, 02:14 PM
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Quote:
Originally Posted by djmas View Post

can some explain what the following means?

[High Speed Video] 1280 x 720 pixels, 30 fps (MP4) (Sensor Output is 120fps) / 640 x 480 pixels, 30 fps (MP4) (Sensor Output is 240fps)

does this mean it records at 30fps and upconverts??? i'm totally lost here

edit--- got my answer... Thanks Chas!

No - camera downconverts (slows down) from 120fps to 30fps @1280 x 720 pixels and from 240fps to 30fps @604x480
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post #26 of 28 Old 10-31-2013, 08:49 AM
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I use the Casio Exilim ZR100 and have been very happy with it.  It's small fits in my pocket, mounts on a tripod and shots at 30fps, 30/240 fps, 240fps, 480fps, and 1000 fps.  The higher frame rates requires more light and in order to achieve 1000fps the picture in condensed.   For golf or baseball analysis 240 is perfect since you play back at 30 your are slowing everything down 8 times.   There isn't any blur of the bat or jello effect.   I've recorded 1000's of swings in full daylight to under lights at the field and even under lights you have enough detail to see your swing clearly to see what needs to be corrected.

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post #27 of 28 Old 10-31-2013, 08:59 AM
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Quote:
Originally Posted by SoonernScout View Post

I use the Casio Exilim ZR100 and have been very happy with it.  It's small fits in my pocket, mounts on a tripod and shots at 30fps, 30/240 fps, 240fps, 480fps, and 1000 fps.  The higher frame rates requires more light and in order to achieve 1000fps the picture in condensed.   For golf or baseball analysis 240 is perfect since you play back at 30 your are slowing everything down 8 times.   There isn't any blur of the bat or jello effect.   I've recorded 1000's of swings in full daylight to under lights at the field and even under lights you have enough detail to see your swing clearly to see what needs to be corrected.

Could you post some videos on Youtube or Vimeo?
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post #28 of 28 Old 10-31-2013, 09:05 AM
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I recently tested another automatic exposure camera to see how well it could perform in high speed video, in particular, the motion blur in direct sunlight.


Post on Kinovea forum.

Low Cost High Speed Video Cameras Capable of Tennis Stroke & Other Athletic Motion Analysis.

The high performance, high speed video cameras, such as the Casio EX FH100, with full manual exposure control, as discussed above, are not currently in production in 2013. They are worth it, but are now expensive and difficult to find.

How about much lower priced cameras with automatic exposure control?

General High Speed Video Cameras with Automatic Exposure Control. To video tennis strokes, low priced, high speed video (> 60 fps) cameras are available. The currently available cameras all have automatic exposure control (AEC). The shutter speed selected by the camera's automatic exposure control might not be optimized to minimize motion blur. In other words, you often get too much motion blur with automatic exposure control cameras. The amount of motion blur from these cameras is not predictable from available information but can always be measured in tests.

Canon Powershot ELPH 110 HS/ IXUS 125 Tests. I purchased a low priced Canon Powershot 110 HS / IXUS 125 camera in order to test it for tennis stroke analysis. It does 240 fps at a reduced resolution of 320 X 240.

The automatic exposure control selects the shutter speed based on the light received from the scene. The specs list the fastest shutter speed as 1/2000 sec, but it is not known if that shutter speed is reached for high speed video mode. Unfortunately, predicting the shutter speed that this camera's AEC might select is not possible without testing.

To test for shutter speed/ motion blur in direct sunlight -
1) Observed the motion blur on a rotating disc.
2) Observed the motion blur on the tennis ball and racket of a tennis serve.

I found that a very important setting for minimizing motion blur was the zoom setting on the lens. The widest angle zoom aperture setting has the fastest f#, probably 2.7. The wide angle zoom produces very small motion blur in direct sunlight - see videos below. The telephoto aperture setting is probably f# 5.9 and produces significant motion blur - see videos below. In fact, the telephoto videos below show that the motion blur from the ball streak is roughly equal to the distance that the ball travels between frames. This implies that the shutter speed for those videos was very slow, roughly equal to the time between frames, 1/240 sec. For these videos, it might also have been important for the AEC that more skylight was accepted by the wide angle field of view than by the telephoto field of view. See note below on light metering.

To attempt single frame advance on Vimeo press the play-pause control as fast as possible. The video image quality after compression on Vimeo is not as good as viewing directly on my computer or on the camera's display.

Widest angle zoom setting - small motion blur
https://vimeo.com/74060780
https://vimeo.com/74060778
https://vimeo.com/74060705

Most telephoto zoom setting - considerable motion blur
https://vimeo.com/74060777
https://vimeo.com/74060779

These tests were under direct sunlight to get a fast shutter. With less light the motion blur will increase. See also other Canon high speed video tests of tennis serves and also a rotating disc test to show Jello Effect distortion and shutter speed.

This camera cost $119, refurbished, with free shipping on sale from Canon. The one I received was in like new condition.
http://shop.usa.canon.com/shop/en/catalog/powershot-elph-110-hs-red-refurbished

The Canon 110 HS camera is capable of showing the fastest parts of the tennis serve with wide angle zoom setting and under favorable lighting conditions. Other Canon Powershot cameras with high speed video might work in the same way. ? Other low cost cameras with high speed video might also produce small motion blur with wide angle lens settings and in direct sunlight. ?

To minimize motion blur - video in direct sunlight with the widest angle zoom setting. Also, have a bright background, include some sky (but not sun) in the field of view.

Note: The Canon Powershot 110 HS in high speed video mode uses Canon 'Evaluative' light metering to view the full scene for its automatic exposure control. Here is a general link on Canon Evaluative light metering. It is not very clear or useful and may not apply to the Powershot 110 HS / IXUS 125.
http://www.cyberscholar.com/canon/camera/index.cfm?page=trainingCenter&product=evaluative_metering&productPage=mod0101&menu=mod_on1
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