# Using video for form evaluation



## rkumetz (Jun 20, 2014)

I originally posted this question here because I am interested in using video for form analysis but for some reason it
was moved to another forum. I am posting it here again in hopes that someone is using a reasonably priced camera
for high(er) speed (1000ish FPS?) video at a decent resolution and under the assumption that this is a forum perused
regularly by people doing coaching:

*While the Casio FH20 digital camera will do video up to 1000fps, the resolution is progressively
lower at higher rates until it is pretty miserable (224x56) at the 1000fps. That being said, it is a
serious bargain and they go for pretty low prices on Ebay.

Is anyone aware of a digital camera or camcorder which can do relatively high frame rates
with better resolution yet does not cost as much as "real" high speed video? *


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## Moebow (Jul 8, 2010)

IF you are just doing form work, I don't think you really need a 1000 fps camera. A standard camera that does video is good enough and a program like "Coach's Eye" or "Ubersense" Will show every ting you need to see. I have a Casio that does the high frame rate and have never used that feature. That would be good for arrow clearance during the shot but as you say resolution is lacking at high speed.

I haven't seen the new iPhones that do 240 fps but that MAY be a thought and is compatable with the "apps" listed above.

Arne


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## naptalene (Oct 8, 2012)

The problem with higher frame rates is disk access times required for higher res files.

What res are you hoping to achieve? At 1000fps for anything near an SDformat I would assume your looking at dedicated drives and preferably SSD drives. 

And the actual codec used will also impact on the quality. I know that doesn't answer your question directly, but it will hopefully give you things to check.


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## rkumetz (Jun 20, 2014)

If I could do 240fps that might work as long as the resolution was decent. The 
Casio goes up to 1000fps but at that resolution it is something absurd like 64x64 which is
pretty much the resolution of a malfunctioning 1972 security camera.

There are a few things I am interested in seeing (for example a very slowed down version of the tab coming off the string
from above or below). I realize that for most purposes that is not essential but there are a few form points that I would like to analyze
and don't have access to HS video.

My preference is to do it with a real camera or camcorder since in the long run an iPhone and the associated data plan will end up costing me
more plus as an engineer I take offense at Apple telling me what software I can and cannot put on my phone. Yep. I am one of THOSE guys!


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## Joe Schnur (Mar 22, 2012)

The 240 fps is full video great pictures use it for coaching analysis my self. Nothing says bad release form like a hi res slooooo motion video and unless you are studying arrow flex 240 fps is sufficient


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## Joe Schnur (Mar 22, 2012)

Data if you download the video with cable is free. Just saying 1000 1200 fps is really expensive


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## aread (Dec 25, 2009)

Standard speed video can be used with a video analysis program as effectively as high speed video. One program is Kinovea. You can advance or reverse it one frame at a time or speed it up. You can draw lines and measure angles.

Best of all, it's a free download.

Allen


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## mirek (Jan 31, 2005)

I agree with Allen. And in last version has speciality tools for archers. I use It with my LX7 camera for me and my archers


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## mike 66 (Jan 21, 2010)

all is good..... is issue i see you need to know just what to look for.and how to correct it...


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## rkumetz (Jun 20, 2014)

naptalene said:


> The problem with higher frame rates is disk access times required for higher res files.
> What res are you hoping to achieve? At 1000fps for anything near an SDformat I would assume your looking at dedicated drives and preferably SSD drives.
> And the actual codec used will also impact on the quality. I know that doesn't answer your question directly, but it will hopefully give you things to check.


My engineer brain requires me to investigate all sorts of things that most people don't really care about. I think that there are subtle movements that are not captured in 30fps video and no matter how much you slow down the playback, 30fps video only took one frame every 33ms so you don't see anything in between.
I would really love to get some higher speed footage of a tab coming off the string from above and below. That would be really cool but you won't see much at 30fps.

If I could get VGA or better resolution at 240fps or greater I would be moderately happy. That is a resolution of 4ms which is ok considering that if your bow can propel an arrow at 200fps and your brace height is (hypothetically) 8 inches, the shot (from release to knock off the string) is "over" in about 4ms. 

The original point of the thread was that since I am looking for a camera to record with I was hoping for some suggestions of cameras with 240fps or higher frame rates at a decent resolution. I am not a smart-phone kind of guy (yes, I did say I am an engineer but I really only want to receive calls on my phone nothing more, nothing less) so an iPhone or Android device would not be something that would interest me. Once I find a camera that can do that Kinovea will be a very powerful tool.


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## naptalene (Oct 8, 2012)

If you look into a camera that can shoot progressive hd it might help. So the screen res could be about 720 but if it's progressive you get rid of interlacing on the feed so each frame is a complete frame, and there's no interlacing?

Just suggestions to try and help.
I've seen an old film camera shoot 1000fps.
It ate an entire reel in seconds, very cool and very awesome footage


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## Joe Schnur (Mar 22, 2012)

You can become a world class archer with out ever looking at video focus on the simple stuff it has the biggest impact . I too am a physicist and can't let my head get into the details or I will be shooting an ok archery bow with massive stabs and 8x scope and won't be able to shoot for crud due to the form issues it would create. Keep it simple as possible don't slow mo evaluate arrow flex and blade frequency etc just shoot and refine form or you will drive youtprself insane


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## rkumetz (Jun 20, 2014)

Joe Schnur said:


> You can become a world class archer with out ever looking at video focus on the simple stuff it has the biggest impact . I too am a physicist and can't let my head get into the details or I will be shooting an ok archery bow with massive stabs and 8x scope and won't be able to shoot for crud due to the form issues it would create. Keep it simple as possible don't slow mo evaluate arrow flex and blade frequency etc just shoot and refine form or you will drive youtprself insane


I will agree with that but at my age with serious astigmatism I am pretty much resigned to the fact that being world class is over-reaching.

That being said there are a lot of technical things that I am interested in and understanding what is going on gives me a nice warm fuzzy
feeling. I think it is important for the rest of us who are teaching and coaching to continue to further our knowledge rather than accepting
the word of the current cult of personality that is handing down the tribal knowledge. As you may suspect, I said "why" a lot as a child.


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## Joe Schnur (Mar 22, 2012)

Got that you can only acheive what you think you can don't let your mind handicap you it is more of an art than a science.


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## rkumetz (Jun 20, 2014)

Joe Schnur said:


> Got that you can only acheive what you think you can don't let your mind handicap you it is more of an art than a science.


I am going to have to respectfully disagree with you here. Archery is all about science including but probably not limited to physics, biomechanics and even psychology.
I am an engineer and I want to understand what is going on. I am not going to teach something that I don't thoroughly understand and I am not going to criticize something a student does as being incorrect unless there is a good reason for it. 

If we take that quasi-zen archery is an art approach then we will all believe the current cult of personality when they say that NTS is a more biomechanically efficient way to shoot regardless of the fact that no substantial proof has been offered. I agree that it is ONE effective technique based on the success of those who use it however there have been and are world class archers who have not and continue to not use it so it is not ONLY way to fly. That means that there is still room for improvement and anything we learn and document is a contribution to fine tuning what we know about form. As I mentioned before, I said "why" a lot as a child and will continue to do it until I take my last breath.


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## Joe Schnur (Mar 22, 2012)

Ok in the spirit of the comment everything Is about science and physics as the physical laws rule everything on the planet what I was trying to say is understanding proper form and why it is better than the 10,000 other ways of doing it . Being able to separate success from an exceptional athlete that can compensate for those form deficiencies is important. My point is that high speed video analysis of arrow flight has been done and is available for study and review. What makes one archers float go to near centered on the x from all over the red is an art . There are lists of things to go after but it is learning from the experiences of great coaches that allow you to make leaps forward rather than trying to scientifically analyze your way to build up the perfect form from scratch. I won't live long enough to do all the research myself I need to use the body of published work on the subject. And build upon that. 

For example arrow spine. I work with the pro's I shoot with and use their knowledge and tools they recommend to make a proper choice. I don't study arrow flight . Fletching I can do trial and error my self since it is as much preference. To call the experts in the field a cult is an insult to those folks. 

Note: I don't accept archery talk as the source of truth. It is nothing more than a sounding board and source of research material these things must either be validated with personal experience or respected experts who's credentials you have come to know and accept. 


Good luck on your journey.


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## rkumetz (Jun 20, 2014)

This thread may be a bit off track since I AM actually interested in analyzing video of parts of archer form to determine the pros and cons of different approaches.
As I mentioned, I like to understand exactly what is going on have some specific interests, questions and ideas.

That being said, I am not afraid of insulting "experts". A real expert is secure in his or her knowledge and is open to discussing the merits of his ideas versus others.
Someone who is a true expert is willing to PROVE that his (or her) ideas are true. If a professed expert expects everyone to take it on faith then they are not
an expert they are trying to start a religion (not to cast any negative light on actual religions and spirituality) and those who mindlessly follow are their cult. 
Plain and simple. I am not saying that YOU object to the pursuit of knowledge but I get a distinct feeling that there are some recognized figures in the archery 
community who would prefer the rest of us to simply follow their lead and stop asking questions. I am not alone in this train of though either. I don't profess that
they are actually wrong but I would simply like to see the science to prove what they are saying. I don't think that to be an unreasonable request.

I find the learning about this sort of stuff to be a big part of the fun. I have been shooting arrows for many years and as I get older my eyes get worse I find that there
are lots of things about archery that I can still be learning about and sharing with both students and others with similar interests. Archery is an addiction but you probably already know that which is why you are here!


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