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Messages - LaPerouseBay

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1
Gear Talk / Re: Apple iWatch with Dawn Patrol SURF TRACKING
« on: January 27, 2021, 01:51:05 PM »
Here is a link to the impeller, with a few comments about the limitations of GPS. 
https://www.rowinginmotion.com/designing-measurement-system-rowing-boat-speed/

Here's Robby on a few videos I referenced.

Average speed is over 18mph.   
https://youtu.be/M4LQqMhdg5E

Gopro on his head, with the speed overlay (GPS at 18Hz).  Gopro cams have the gauge in their software somewhere.  It will be far more accurate than an iWatch and Waterspeed app, recording "~1Hz"  Particularly for air drops.  Spikes like an air drop are when I get very skeptical.  Hence the running graph.  I've seen some weird stuff on my 1Hz running graphs.   
https://youtu.be/0fqaT7LOCvY?t=193

2
Gear Talk / Re: Apple iWatch with Dawn Patrol SURF TRACKING
« on: January 26, 2021, 04:17:15 PM »
Beasho,

Here is the full video.  In my sport, we aim to flatten that speed line.  We avoid dropping straight down the waves, unless we can "make the next section" (to use surfing parlance).  That's why I whipped up that graph in Racerender.  If the speed graph drops precipitously, I'm about to do something wrong....   

In surfing, a scrolling speed graph will help illustrate the accelerations as you turn down the line.

That said, it's important to realize that all those fancy numbers are relative to the ground, not the surface of the water...  The effect of angling across a wave would be easy to see.  You should do it on your foil at Mavs.  I'll send you the template for that graph, it's easy to adjust for your speeds. 

That long ride Robby did averaged 18mph.  He was flying across the wave, just as Laird does on foil at Nazare'.  Nothing against air dropping, then straightlining big Mavs, it's all amazing to everyone. 

If you really want to claim speed across the water (or air) using GPS - accurately, you gotta go mechanical.  Rowers have been using them forever.   

https://youtu.be/B_FlTgM_Xw4

3
Gear Talk / Re: Apple iWatch with Dawn Patrol SURF TRACKING
« on: January 26, 2021, 03:42:48 PM »
Garbage in, garbage out.  Telemetry scrolled real time (like a scope on a hospital heart rate monitor) will show you the error of your ways.  Flatlines at 18Hz is one thing, at "~1Hz" would give new meaning to the concept of  "data smoothing." 

Here is an example of a real time speed graph, overlayed on video.  It scrolls thru 10 seconds of telemetry (synched automatically on the video file, via gopro).  Your gopro Max will do a speedometer overlay with the same data.  (That's what Robby Naish used on his wingfoil speed at Maliko video).  Both cams sample at 18Hz.

See all the missing points on the line?  That's 180 points on that line, IF none are missing. Flatlines are missing points.  It's very common among GPS telemetry.  (That's why the DJI pros go up to 100Hz).   

Your iWatch is struggling to send 10 points to the Waterspeed app.  Then the app averages it all.     

The iWatch antenna is mounted to a moving object (wristwatch), Gopro antenna is mounted to my head.  We have excellent GPS signals here, as do you.  The helicopter guys have a nifty site to prove it.   https://www.uavforecast.com/

So, those air drops Haley is doing may very well be 34mph.  But the data points you are using are weak at that rate of change.  Therefore, top speeds spewed by the Waterspeed app are wildly speculative.  You know it better than I do with your math background.

When you put all the data alongside the video, it's easy to see.       

4
Gear Talk / Re: Apple iWatch with Dawn Patrol SURF TRACKING
« on: January 26, 2021, 10:52:50 AM »
Then someone puts peanut butter in the chocolate.  We don't even know who.  Maybe it was this guy????
Ken Winner (not him in your picture).

The Waterspeed app allows for CSV downloads but at ~ 1 record per second.

Garbage in, garbage out.  Telemetry scrolled real time (like a scope on a hospital heart rate monitor) will show you the error of your ways.  Flatlines at 18Hz is one thing, at "~1Hz" would give new meaning to the concept of  "data smoothing." 

You live a stone's throw from Silicon Valley, Ivy league math background, yet continue to use the weakest telemetry/software available.  Shame on you.   :)   


5
Gear Talk / Re: Apple iWatch with Dawn Patrol SURF TRACKING
« on: January 24, 2021, 10:32:29 AM »
For those new to the surf data game let me put this in context.
TRACE was recording @ 5 Hz where the iWatch is typically 1 Hz.   

Your Gopro records GPS at 18Hz.  Overlay the telemetry on video (with a real time running speed graph).  Trust me,  you will gain a new perspective on peak speed.
     

   

6
Gear Talk / Re: Apple iWatch with Dawn Patrol SURF TRACKING
« on: January 24, 2021, 07:18:10 AM »
This is probably The Fastest longest wave ever recorded.  at Half Moon Bay, on an iwatch...without a tow in...

Fixed it for you...

7
Gear Talk / Re: Apple iWatch with Dawn Patrol SURF TRACKING
« on: January 23, 2021, 08:59:44 PM »
This averaged 21 mph for 1/2 a mile. 

Robbie Naish surfed over a kilometer at over 18mph on an SUP.  Easy to find on the Google.  It was almost 7 years ago.

Laird and many other pros have likely gone longer and faster on foil than Haley's Mavs ride.

https://youtu.be/7fWhI3xeo1U

8
Random / Re: My action cam evolution
« on: January 07, 2021, 01:08:45 PM »
There are only so many places with truly good wind in the US and the World.  Cape Hatteras, The Gorge, San Francisco Bay Area, Corpus Christi, and Hawaii.

South Africa is king when it comes to big downwind. 

https://youtu.be/tv_3mxUAcnU

9
Random / Re: Robert Redfield - CDC - Covid
« on: December 17, 2020, 12:10:35 PM »
^Nice.
 
As I'm sure you are aware, the soreness is a good thing. 

Here is an interview that answers some other common questions.

https://youtu.be/eK0C5tFHze8?t=1397

I'm at the back of the line (89/100) in this nifty site:

https://www.nytimes.com/interactive/2020/12/03/opinion/covid-19-vaccine-timeline.html




10
Random / Re: Robert Redfield - CDC - Covid
« on: December 16, 2020, 10:19:30 PM »
Thanks for that link Rando, that was fascinating. 

https://youtu.be/NdukJ8iG84s

11
Random / Re: Covid-19 - the Second Wave?
« on: December 09, 2020, 08:03:04 AM »
^Indeed. 

Here's a dose of yesterday's "daily distortions" from the NYT.

Youtube and Facebook are allegedly censoring as well.     

https://www.nytimes.com/live/2020/2020-election-misinformation-distortions#a-senate-hearing-promoted-unproven-drugs-and-dubious-claims-about-the-coronavirus.

Next up: Rachel Maddow will link Ivermectin to Russian meddling.   

12
Random / Re: Covid-19 - the Second Wave?
« on: December 08, 2020, 08:12:03 PM »
This should be interesting.

https://youtu.be/Tq8SXOBy-4w

This is what Dr. Kory deems offensive.  Starts at about 11:00.   

https://www.c-span.org/video/?507035-1/senate-homeland-security-committee-holds-hearing-covid-19-pandemic&live

13
Random / Re: Apple Silicon
« on: November 21, 2020, 09:35:50 PM »
...When I need a new mini they will be dialed...

And hopefully will let you run the new shiny $799 BlackMagic eGPU (or any eGPU for that matter) bought to supplement Davinci Resolve 17 and Rhino 3D because right now you'd be F**ked.


Hmm, Am I mistaken in assuming that BM has a specific version of Davinci 17 for the M1?  Therefore - Davinci 17 should run fine on the new Mini?  I think that's what this guy is saying, but I'm no expert...   

https://youtu.be/p2B8uksMFRU?t=84

14
Random / Re: Davinci Resolve 17 - Incredible
« on: November 21, 2020, 11:24:20 AM »
Yes, primarily north shore though.

Most of the alpha surfers prefer to use a paddle when foiling downwind.  I think wingers do Ka'a point and harbor in the mornings, then the expert wingers will hit Maliko. 

Big wind this weekend, my head will be on a swivel.   

15
Random / Re: Apple Silicon
« on: November 21, 2020, 11:05:22 AM »

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