https://www.youtube.com/watch?v=hGXQgxLJ3LA
I know that slo-mo shows a lot that we don't see with the naked eye....but...
Do you think it is normal that there's such a big "loop" above the arrow?
I ask only because I never seem to be able to get the "nock high" out when tuning...
The way you shoot--I wouldn't worry about it.lol.
Pretty cool Curt, I wonder if the loop is formed because the string silencer is traveling slower than the string itself due to it's higher air resistance.
Interesting video. Strictly as a guess; I would think the 'loop' forms because the string hand is higher than the middle of the bow.
It is cool watching the string go through its gyrations regardless of the 'why'.
I think what you see ( loop ) is mostly from the wide angle camera.
I read somewhere that unless you are using "professional" quality video equipment, that in slow motion it is "averaging" the frames or something like that. It gives a misrepresentation.
As T Sunstone said, it could be from a wide angle lens too. I am no expert by any means.
It appears that the initial thrust of limb recovery caused your arrow to go forward, fast, and that speed of recovery lagged behind the arrows speed of carrying the string forward, until it caught up.
If so, that brings into question the aspect of longer power stroke. As seen here, in this one motion photo, the "power stroke" was not continuous for the length of the drawn shaft.
Hmmmm
ChuckC
One thing that stands out to me is the apparent downward bend of the arrow as it is drawn. That MAY be due to the camera/lens optics involved, but IF the arrow is being bent down by the draw technique, that will make it "bounce" upward giving that tail high arrow flight that you see in the video.
Again, hard to say for sure, but this is common to vertical (nock high) tuning problems.
Arne
In the video of the pheasant hunt a couple of days ago, when they showed the shot in slow motion, their string had a lot of movement.
I would say it is normal, video the bottom limb and I bet it does the same or similar.
I have seen a couple videos that show way crazy string action. It is normal from what I have seen in the other videos. It just happens so fast, we can't see it.
There was one video I have seen that will make you wonder how the string ever stays on the bow when shot!
Bisch
Thanks for the video! Fun to watch and speculate what is going on.
Ken
what did you record that with?
I can't offer a knowledgable opinion on this question, but that is amazing, Curt. Thanks for sharing it.
Yea Curt, that lens has a bit of a "fish eye" convex to it and may be distorting the image of the string a bit. JMHO
Some good thoughts here fellas....
Terry S....I believe some of it is, but I believe it's not a whole lot because it would be distorted on the way back as well.
Moe bow, I believe the the slight bend is from the "fisheye" effect of the lens. I don't have the nock high problem tuning any of my other bows.
Jim G., it was filmed with a Sony Action cam in slo-mo. Then I slowed it some more while editing.
I plan to do a whole lot of cool stuff with it in the future!! Really a cool little camera...
Curt, I'm guessing but a couple things stand out from the video, 1. one is it looks like the camera is fish eye from the arrow, it has a curve in it as well, 2. The beaver balls seem like they are holding the string behind due to the difference in aero-dynamics of the two causing the large bow in the string(would be nice to see if the bottom of the string is doing the same at the silencer!
(http://i1085.photobucket.com/albums/j435/Tloran/string_zps6fae4134.png) (http://s1085.photobucket.com/user/Tloran/media/string_zps6fae4134.png.html)
(http://i1085.photobucket.com/albums/j435/Tloran/5862c2a8-ff0d-4a4f-b979-207323d483f0_zps150f8ec1.png) (http://s1085.photobucket.com/user/Tloran/media/5862c2a8-ff0d-4a4f-b979-207323d483f0_zps150f8ec1.png.html)
Curt, what is that hanging off the back of your silencer, wind checker, maybe a drag factor as well?
Thanks for sharing, cool video.
QuoteOriginally posted by the elf:
The way you shoot--I wouldn't worry about it.lol.
Ha! You may change your mind when you see the next clip I'll post later :knothead: :banghead:
I still think it is some kind of distortion either from the lens or the slow motion program.
Given how a bow works, I don't see any way that the arrow can be going forward and part of the string is "lagging" behind. Now side to side as it comes off the fingers I can understand, and as the bow comes back to brace as the arrow leaves I can understand, but not what we are seeing. :dunno:
On an unrelated note, your slow-mo video also shows a great example of how to properly continue to pull through the shot to its conclusion. I wish I could do that. I always seem to pull to my anchor, stop and then release. Nice form!
my initial thought was that maybe your bottom limb is way stronger than the top
QuoteOriginally posted by Hermon:
I still think it is some kind of distortion either from the lens or the slow motion program.
Given how a bow works, I don't see any way that the arrow can be going forward and part of the string is "lagging" behind. Now side to side as it comes off the fingers I can understand, and as the bow comes back to brace as the arrow leaves I can understand, but not what we are seeing. :dunno:
That's a good point bud, I was thinking the same thing....how can the middle of the string be ahead...interesting...
You can see a lot of the distortion Sean B noted in the string during the draw. You know the line of the string is "straight as a stretched string", but it appears curved as it is drawn, befor ethe shot.
QuoteOriginally posted by moebow:
One thing that stands out to me is the apparent downward bend of the arrow as it is drawn. That MAY be due to the camera/lens optics involved, but IF the arrow is being bent down by the draw technique, that will make it "bounce" upward giving that tail high arrow flight that you see in the video.
Again, hard to say for sure, but this is common to vertical (nock high) tuning problems.
Arne
How does one overcome this issue? Not to Hijack the thread, but this is something I struggle with. I've video'd myself plenty, and I can't see a bend on the arrow. It goes away completely when I shoot 3 under, both bareshaft and paper tunes are bullets. It bugs me... I feel like this is what's keeping me from getting my spot league scores into the 270's.
Dan,
Could be a couple issues. You say it goes away 3 under so first place to look is allowing the index finger to press down on the top of the arrow nock.
String pinch can do this and also, too much tension in the wrist which can cause the index finger to press down.
Be sure your fingers are as perpendicular to the string as possible, hand, wrist and forearm relaxed. You MAY want to try a finger spacer to see if that helps.
Arne
Film someone else shooting that same bow. See if there is a difference.
Arne,
Thanks for the advice. I know I stay perpendicular to the string, and don't twist or stress my bowhand at all.
I also know I keep my hand pretty relaxed... That's why I get string pinch like a mofo. I've never made an effort to fight it, seems like it'd introduce stress to the hand if I tried to keep from pinching the nock. I shoot a glove, I'll try a spacer in there and shoot bareshaft some today.
Could the arrow be pulling that portion of the string forward as the silencer slows the upper portion down. I wonder if a loose knock would look the same,or a string with no silencers. It is always cool to watch things like that. I think some follow up video is in order.
QuoteOriginally posted by Mike Gerardi:
Film someone else shooting that same bow. See if there is a difference.
I'll have to let Cade shoot it and see bud.
QuoteOriginally posted by maineac:
Could the arrow be pulling that portion of the string forward as the silencer slows the upper portion down. I wonder if a loose knock would look the same,or a string with no silencers. It is always cool to watch things like that. I think some follow up video is in order.
Nock was very loose bud. I always shoot what most might consider too loose. This one was even looser...
Great discussion. I would try to get both limbs in the next video too. I'll bet you see some weird stuff there too.
Ok, scratch that theory. I love puzzling this type of stuff out. I wonder if the bottom string looks the same?
It may be a while(busy, busy), but I will try to get top and bottom in the same vid.
While I have no conjecture to offer up, that is a very fun video to watch! Thanks for sharing it Curt. :thumbsup:
Please also re-position that camera to show from the left (unobstructed) side so we can see a true representation of the string / limb recovery / arrow motion.
ChuckC
QuoteOriginally posted by moebow:
One thing that stands out to me is the apparent downward bend of the arrow as it is drawn. That MAY be due to the camera/lens optics involved, but IF the arrow is being bent down by the draw technique, that will make it "bounce" upward giving that tail high arrow flight that you see in the video.
Again, hard to say for sure, but this is common to vertical (nock high) tuning problems.
Arne
I saw the bend as well, Ken Beck mentions that in MBB volume 1 I think. I use 2 nocks for carbon shafts on one of my recurves due to a nock high issue, that bow is near even tiller though shooting split finger.
I'm sure the weight of the silencer and wind detector cause the loop. Skinny string too? For even a lighter string.
I am with Arne, it appears there is pressure on the arrow and a slight bend. Perhaps it is an illusion.
I watched a long bow video a couple of months ago that had the same loop. Very consistent to what you have captured on video.
I will try remember where I saw it.
Billy
Very cool video.
There's no way for the string to have that much slack.
The limbs will always keep tension on the string.
The weird "loops" we're seeing is caused by the way digital cameras scan the image while the string is in motion.
...slightly similar to the "rubber" pencil trick.
I think it is largely due to the type of sensor in that camera, and the way it refreshes the frame.
If you look at GoPro type footage (I'm not suggesting that this was shot with a GoPro) of helicopter blades or airplane prop blades, for example, the blades will frequently render curved or bent, even though the blades aren't bending in that manner in reality.
This typically comes from using cameras with certain types of sensors that don't incorporate "global shutters" like many professional motion picture cameras do.
I'm not an expert in motion picture camera design and engineering, but I am a cinematographer by profession.
Interesting, I just saw my friends pic the other day...
You guys mean like this???
(http://www.tradgang.com/upload/ryan/1970440_10203180427781137_2134025115_n.jpg)
So I googled for more info and found this image on the internet...
(http://www.tradgang.com/upload/ryan/helicopter.jpg)
Staci and I have seen a few images of compound strings that look like a wet spaghetti noodle on the shot (half the string "looping" forward and the other half "looping" in the opposite direction. Very interesting...
Ryan'n photo's posted and Zradix's comments back up my theory of distortion.
Think about it. What propels the arrow? Forces from the string. Where does that energy come from? The limbs. There is no way the arrow can be accelerating faster that what the string is pushing it. The silencers cannot have slow the part of the string where they are attached without slowing down the string between the silencers (as I am sure there is one on the bottom of the string also) without the arrow having it's own rocket engine in it (which I doubt it does). I feel that the reason the silencers seem to be lagging behind is in the camera sensor or editing software.
Now when the arrow is gone and the remaining energy is being dissipated, then we will see all kinds of string/limb movement.
Curt, I'd go with Major's explanation and Ryan's great visual in my opinion. I've seen a lot of high speed shots of archery gear in action on youtube, TV etc. using professional equipment and while there is definitely a lot more oscillation than one would expect, I've never seen anything like that in all the "real" high speed shots. I don't think it would be physically possible for the string to be "ahead" of itself until after it hits brace. Think of the force of the limbs applied to the string, that's what forces the arrow, so the string would have to stay relatively in line with that force at least as long as it's in contact with the arrow...or the arrow would not move. After the limbs hit brace though you can see that type of funky gyrations pretty plainly high speed. Just my $.02.
Dang, Hermon beat me too it while I was typing. Agree 100% Hermon ;)
I think the bend of the shaft is the camera as well, I watched the bunny hunt photo the film came from and the shaft looks bent just being held. At 42 seconds into the film-crazy!
Curt, I know you already addressed the theory of downward pressure on the arrow, stating that the appearance is most likely due to fish-eye effect. However, I too have nock high no matter what, and have never been able to break the habit of downward pressure with my index finger. The fact that your issue goes away when shooting three under sure supports the theory. Might be worth further consideration. With that said, if Joe's thoughts are worth $.02, mine are probably in the red. :thumbsup:
Ryan's photo shows exactly the phenomenon that I was trying to describe caused by the sensor design typical of prosumer or consumer cameras.
To get truly high quality, undistorted action shots, a camera like a Photosonics 35mm film camera http://www.photosonics.com/4c_cam.htm or a digital camera like a Phantom Flex http://www.visionresearch.com/Products/High-Speed-Cameras/Phantom-Flex/ would be necessary. Both of these are expensive image capturing solutions, however.
This video shows some good examples of various high speed frame rates, and gives a basic explanation of how a Phantom Flex works. http://vimeo.com/48571597
Good stuff fellas!!