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SLP AND SHOULDER , ELBOW, WRIST PATHS

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gordonjudd
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SLP AND SHOULDER , ELBOW, WRIST PATHS

#31

Post by gordonjudd »

The intervals are precisely 0.2s (video frame time anyway),
Dirk,
Does that mean that you marked every 5th frame in PAL videos (that have frame intervals of .04 seconds) to get your path plots or were you able to get de-interleaved frames that would have a frame interval of .02 (not .2 seconds)?

My plot of Tim was taken from a NTSC video that had a frame rate of 30 fps. You can see there were about 7 frames that were marked to get the hand path in that plot, which means it only took about (7-1)/30 (.2 seconds) for Tim to make his forward cast.

I see a similar number of solid lines on your plots which would imply an interval of around .04 seconds between them since I would expect the time to make a forward cast would be in the same ball park for Stefan and Fredrik as it was for Tim.

Gordy
John Waters
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SLP AND SHOULDER , ELBOW, WRIST PATHS

#32

Post by John Waters »

Hi Dirk,

The shoulder is certainly an important pivot in distance casting. It is interesting to watch Steve and Tim cast, both of whom rotate their shoulder powerfully and have done so for their casting careers. I first saw Steve cast as a 16 year old and his pronounced shoulder roll was distinctive then. His brother Tim has the same technique. The wrist dip shown on the various casters portrayed in this thread is collectively prominent but the key is not that the wrist follows a concave path, the key is what is generating that concave wrist path. I concur completely with Gordy's comments.

When Steve casts fly accuracy you will see that his shoulder action is more pronounced than most other casters. That is one reason why he is such a successful accuracy caster. Most people view his distance casting technique but when you analyse both his accuracy and distance casting technique you will identify that very important similarity. Technique fundamentals underpin the amount of line you are casting and the top casters personify that. I believe that the best casters ensure that their shoulder both drives and stabilises their elbow and wrist pivots throughout their respective casting paths, irrespective of whether they are casting a 5 weight line 40 metres, a 38 gram line 70 metres or a piece of wool to a target 8 metres away. I might add that the role Steve's shoulder plays in casting technique is also visible across all types of casting. He employs the same technique fundamental in his plug casting, being particularly noticeable in his 18 gram accuracy casting. A cursory analysis of Chris Korich's accuracy and distance technique will identify the same casting fundamental. As with Steve, same driver is visible irrespective of what rod Chris is using.

There are many different views on haul timing, length and purpose. I like to bend the rod with the casting hand and have the haul not add to that bend, but delay rod straightening. In my opinion, the start position of the haul is critical. As to the end position of the haul hand, where the haul hand releases the line and the speed the haul hand is moving at the line release point are my foci.

John

PS I'm old, ugly and as some have stated, ignorant; so view my comments accordingly. Life is far too short to be taken seriously.
Dirk le Roux
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SLP AND SHOULDER , ELBOW, WRIST PATHS

#33

Post by Dirk le Roux »

gordonjudd wrote: I see a similar number of solid lines on your plots which would imply an interval of around .04 seconds between them since I would expect the time to make a forward cast would be in the same ball park for Stefan and Fredrik as it was for Tim.
_____

I do not have any videos of casters using a 170 distance style where the rod finishing position might be more horizontal and be a counter example to the typical release position you see with good distance casters in the U.S. so this observation of seeing an upward rod angle at the release point is probably not true for all casting styles.

Gordy
Hi Gordy

I don't have an idea of the exact time frames, PAL, NTSC or whatever. I use Windows Live Movie Maker to capture frames and the intervals are for example 09:30, 09:50 etc. Not sure if that is exactly in seconds. I said in my first post the plots CONTAINING INTERRUPTED LINES are at the same intervals, with the interrupted lines falling in between the steady intervals. So if a graph does not display an interrupted line, don't take it as representing steady intervals (i only started the steady intervals with the ones I did later on, to get a handle on speed as well).

The plots of Paul, Ronny, Magnus and Fredrik surely qualify as 170 style, and do display the same down-up.

I agree with your other inputs, as well as those of others. Maybe the truth lies somewhere between and within all of that.

All the best,
Dirk
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gordonjudd
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SLP AND SHOULDER , ELBOW, WRIST PATHS

#34

Post by gordonjudd »

I use Windows Live Movie Maker to capture frames and the intervals are for example 09:30, 09:50 etc. Not sure if that is exactly in seconds
Dirk,
I don't think they are in seconds. The PAL system uses a frame rate of 25 fps so the frame interval is .04 seconds not the .2 seconds you inferred from the MovieMaker tags. Some software will allow you display each interlaced frame and thus get frame rates of 50 fps (or .02 seconds intervals), but I doubt that MovieMaker has that capability.

Thus I think your markers show how things are changing every .04 seconds not the .2 second value you gave in that post.

Gordy
Dirk le Roux
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#35

Post by Dirk le Roux »

Gordy

I checked again. From 0:20 to 0:40 for instance was six advance clicks of the mouse on the Windows Movie Maker. If that's any help. It seemed some frames didn't advance between single clicks, which probably depends on the frame rate of the recordings and/or the interleaving thing you mentioned. Still getting the same accurate enough picture of motion and speed through a cast's progression every sixth click (or third with the in between ones), though!

The paths are automatically smoothed by Archicad's spline tool. :cool:

I've begun to think that, apart from the force dynamic benefits, the down part helps make room for a lower tip path arc trough the maximum vertical cord length part of rod rotation (see plots of Ronny Landin and Alejandro showing rod and tip path) while the up helps maintain a straighter tip path as the rod progressively unflexes than would be possible without it. I think that's part of what Paul meant by rod driven. The up also helps ending up with a tip position closer to the straightest part of tip path and thus narrower loops.

All the best,
Dirk
Dirk le Roux
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#36

Post by Dirk le Roux »

The unit in the moviemaker is in seconds Gordy! I timed with a stopwatch a few times over fairly extended periods and then even longer hitting the mouse button and stopwatch simultaneously and the two correlate, give or take a few hundreds of a second through error between two different fingers. Reading on WLMMaker 41:16, reading on cellphone stopwatch 41:2 (cant show 100ths).

All the best,
Dirk
Dirk le Roux
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#37

Post by Dirk le Roux »

Actually that was the most accurate i've ever seen "Microsoft Time" :yeahhh:

"Your programme will close in 1min 30s, Your programme will close in 1min 30s, Your programme will close in 1min 30s, Your programme will close in 1min 30s, Your programme will close in 1min 30s, Your programme will close in 1min 30s, Your programme will close in 1min 30s, ..." Yeah right
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VGB
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#38

Post by VGB »

Dirk

The frames that did not advance may be caused by where you get the source material from. The video may have had some frames removed to help compression for internet use.

regards

Vince
Casting instruction - making simple things complicated since 1765

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Dirk le Roux
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#39

Post by Dirk le Roux »

That makes sense Vince
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