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Underwater video
#11
I keep nervously waiting to see something really frightening and I’m so glad I didn’t!

I was raised in Florida and was never afraid of the water. Things started changing for me after Jaws...

I lived in Hawaii in the early 80s and I did go in the water there but I always had that stinking bug in my ear whispering and keeping me on edge
monkeyfoot
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#12
ERLH
Not speaking for Stern but I'm not sure I'd WANT to see what is following ?????
Stay Tuned
rvpopeye



Weirdo Overlord  YARC 
ROOIRIA  
15 "Stinkin'Badges"  a "Full Monty Badge" 2 "Just Ignore Me" clusters  10 "Pine Cone" clusters  , one "Stinkin' Badger" and 7 of the coveted "Flying Manure Spreader"awards
(What a "Stinkin' " honor !)
 


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#13
My concern of dangerous ocean life is currently the numerous stingrays, and bacteria laden polluted water infesting my ears causing infections.  I figure for every shark I see, that hundreds of sharks have seen me, and carried on doing their thing, leaving me alone.

  If a large hungry Shark decides it wants me, I hope it finishes the job quickly. I would so prefer to lose my life being eaten by a shark, compared to eaten by cancer or killed by some drunk or texting driver.

  I'd love to see a shark in my videos.  Hopefully its presence and the subsequent screen shots I would laminate and post at every beach I surf, would reduce the severe overcrowding in the water these days. I wish there were much more regular shark sightings, except for the fact that the lifeguards would close off the ocean entirely for miles in each direction. Asinine overreaction,  but par for the course these days though.

 A kid got attacked nearby, the first day of lobster season last year, when he had a lobster in his hands and was reaching for another one, oblivious of his surroundings.  The media circus afterwards was contemptible, but the crowds, once they reopened the ocean, were a fraction of what ithey were before, which lasted for only a few days, but it was awesome to have fun conditions and not a zillion idiots out competing for the waves available, and getting in the way.

Right now, the waves are quite good with a swell from what was hurricane Barbara, but holiday weekend crowds turn my stomach, and I do not want to deal with beach crowds, or in the water crowds, or parking, or people in general.  The Stingrays are quite prevalent and people are getting tagged left and right,  yet the tourists keep infecting the shallows anyway.

As far as a rearward facing camera, that is definitely in the cards at some point. I've considered making a hull mount to face the fin aimed backwards too but I think turbulence would often obscure the view.

While I've been wanting to see video shot from this below and behind angle, since the early 90's, it only became po$$ible for me, fairly recently.

The new 3d printed turbucled high aspect ratio fins that I have been receiving for testing from a guy in Australia have been working very well in my longboard and non turbucled high aspect ratio fins are working very well in my shortboard too.  High aspect ratio creates less drag, and the turbucles also prevent 'upwash' which reduces the tip vortex, and the tip vortex is like a thin weak rope that attaches to the tip of the wing/fin and increases drag.  Turbucles also allow higher angle of attack before stalling and the stall is gradual, not abrupt. Once fully stalled the drag is a fraction of a regular fin too.

The winglets one sees on the tips of airplane wings can reduce fuel consumption upto 5%, by reducing the tip vortex and also allowing a shorter lighter weight wing to be able to produce the same amount of lift at the same angle of attack.

Most every video I shot from this angle was with a 3d printed high aspect ratio fin.  The fin will, when loaded / producing lift, coalesce the bubbles already in the water and form the visible tip vortex.  The tip vortex is always there when the fin is loaded, but not always visible.  The more 'efficient' the fin, the smaller and shorter the visible tip vortex 'should' be.

The one video posted, with the 'dol-fin', which is the standard raked style of fin in used on surfboards  the world over, was used with a 'universal' camera mount.  I was expecting it to have an almost everpresent visible tip vortex, but found it was just slightly more frequent and of longer duration than HAR turbucled fins.

This 'universal' mounting system which was basically  a requirement for a non turbucled fin, however was a good learning experience, in furthering the drag reduction and precision of the non universal ones.  The 'universal'  camera mount  is obviously tilted, and slightly to the side of the fin when it is not moving. A newer more precise  'universal' one is being built.

Its use on the raked fin had the camera farther back behind the board, a field of view I liked more, so the latest mounting system holds the camera even further back.  The new mounting method is not kinked and should present less drag and be slightly deeper too.

One guy I know was trying to capture similar video, using a smartphone attached to one rail fin, aimed at the other rail fin.  He said it affected the performance of the board greatly, to the point is was not even worth trying to surf.  He said that the visible tip vortex would seem to come from behind the  fin, and grab the fin tip during harder turns.  While my video seems to show it forms at the tip and stretches out from there. I've not seen his video.

How far back the visible tip vortex of spinning bubbles is being dragged, is unknown at this point, and the rearward facing camera should solve some of that.  But the more distant camera from board might also to some degree.  It is rather time consuming to change the orientation of the camera on the rod, not something I would want to do on the beach.  Methods to simplify this task, have been tabled for now.

The guy in Australia who has designed and printed these high aspect ratio fins, has installed a 360 degree 'fly' camera within the hull of one of his boards, but it does not show the hull of the board when submerged, though it does when dry. It shows the fin just above its base, and 360 degrees of the ocean bottom too.
 It too is pretty neat video and the water clarity he has used it in as about 100x better than what I have captured.  I prefer to watch my angle more so, but  his Aussie water clarity has been many fold superior.  He has hunted for the visible tip vortex but rarely has found it, and we are using the same fins, so I thiink it is possible it is more visible farther behind the fin, and his camera with its 360 field of view is less likely to show it, and the vortex is likely often partially hidden behind the fin itself.

Here is a short clip of what he has captured.  One can grab the screen with their mouse and move the field of view, or with a smartphone just aim it in different areas.

https://www.youtube.com/watch?v=TbiGDXvOfGU


The presence of the visible tip vortex in and of itself does not really prove that there is any advantage to a fin which produces less of one.  Surfing is frequently about slowing down, to stay near the steeper more powerful  breaking part of the wave, rather than attaining maximum possible speed and outrunning it with minimal possible drag. Drag is control, to some degree.  The goal should be maximum  control with minimal drag, but really surfing is all about having fun, which is subjective. 

These bizarre looking High aspect ratio fins are allowing me to have more fun, and not just from the novelty of feeling and looking different. It's both funny and frustrating, how incredibly resistant surfers and surfboard designers are to such an unstandard looking fin.  I get so many surfers full of themselves and their design knowledge, skoffing at these fins when they see me en route to the ocean, but then come upto me afterwards looking at fin and my board with 'magic carpet' types of compliments.

The pic below shows one pretty good visible tip vortex on a fin that was somewhat more prone to forming them, and lighting conditions more prone to showing them.


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[-] The following 1 user says Thank You to sternwake for this post:
  • Everyroadleadshome (07-06-2019)
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#14
Great product testing method !
I'd like to see one on vid too.

SKUH KUH KUH KUH KUH !
Thinnin' out the crowded spots.....

I use a similar technique at my fishin' spot to discourage the swimmers.
They all ask what I'm fishin' for.
1 Shark - 2 Stripers - 3 Blues - 4 Cod (Tuna are actually #1 on the days out after them !)
And I do like catching the big stuff.
(And yes there were a few caught there recently including a 6' tiger.)
It didn't work today but yesterday , just-like-magic.

I've put the bite on lots of sharkies.
None have ever put a bite on me.
It helps to be careful.
Stay Tuned
rvpopeye



Weirdo Overlord  YARC 
ROOIRIA  
15 "Stinkin'Badges"  a "Full Monty Badge" 2 "Just Ignore Me" clusters  10 "Pine Cone" clusters  , one "Stinkin' Badger" and 7 of the coveted "Flying Manure Spreader"awards
(What a "Stinkin' " honor !)
 


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#15
I miss fishing.

I don't have much interest in doing so in California, but back when camping along the Pacific  in Northern Baja was still relatively safe, that was my major source of protein.

Last time My van was in Jersey, I was eating a lot of fresh Striper, and when I was a kid the blues running through the surf while we were surfing was scary as F, they'd move in so quick and hit at just about everything.  Might be where I became disaffected with wearing/adorning anything shiny, ever.  Had some buddies whose wrists got hit when wearing watches when the blues started running.



I didn't know tiger sharks worked their way that far north.  This map seems to think Cap cod is as far north up the NA seaboard they go.  I thought they stayed in the tropics. 
[Image: tiger-shark-map.jpg]

this 2008 map did not account for climate change I guess
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#16
Thanks for the education and very cool. Ideas Stern. I’m sure we would all love to see more as you make them
monkeyfoot
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#17
The Gulf Stream gets deflected a bit by Cape Cod but it's still heating up some here anyhoo.
Lobbies are slowly moving north to Nova Scotia , still hanging in here but a bit more offshore..
BLUES are nasty business . Chomp chomp ! Silver OR white , take it off.
Schoolies are in ? blues follow .
Mini sharks fer sure.
Keep a club handy if planning on catching any.
BEFORE removing da HOOK ? BOP !

Green crab invasion is threatening the clam stocks too.

The airborne weather is getting flakier but the sea tells the tale. It's heatin' up .
The sea lanes above Canada are opening up more and earlier.
Stay Tuned
rvpopeye



Weirdo Overlord  YARC 
ROOIRIA  
15 "Stinkin'Badges"  a "Full Monty Badge" 2 "Just Ignore Me" clusters  10 "Pine Cone" clusters  , one "Stinkin' Badger" and 7 of the coveted "Flying Manure Spreader"awards
(What a "Stinkin' " honor !)
 


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#18
I grew up just south of Boston and our neighborhood was a peninsula, the tip of it being a large baseball field/park.  I grew up fishing, lobsters and clamming down there and we used to love fishing for the blues when they were running.  Red dot was our house,  yellow dots was the baseball field we fished from


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#19
Compass Lounge
Stay Tuned
rvpopeye



Weirdo Overlord  YARC 
ROOIRIA  
15 "Stinkin'Badges"  a "Full Monty Badge" 2 "Just Ignore Me" clusters  10 "Pine Cone" clusters  , one "Stinkin' Badger" and 7 of the coveted "Flying Manure Spreader"awards
(What a "Stinkin' " honor !)
 


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