Thursday, March 28, 2013

GoPro Camera mount for kite lines




Problem:  

You want to take pictures or video from your kite or your lines.

Solutions:  


  • Buy a $40 mount that is nice quality connects quickly and you are up and running. 
    • Downside: very little adjustability and is typically "in your face" and too close.
  • Mount the camera to the kite
    • Downside:  Who is that speck?
  • Make your own for cheap that is adjustable and super stable
    • Downside: Possible ridicule, most likely jealousy.
I thought I was the creative maker type and opted to make my own.

Requirements:  

  • Easy to install on the kite
  • Stable and resists twisting or wobbling
  • Adjustable to allow positioning up/down the lines.
  • lightweight
  • sturdy enough
  • cheap so that if I destroy it, I can build another
  • materials must be relatively easy to get at a hardware store
  • Should break down for travel




Materials:

  • 4 - 3/8"x3'  Hollow Carbon fiber Kite struts -  available at any kite shop
  • 4 - 3/8" Inner Diameter plastic Tee for drip tubing.
  • 4 - tiny brass bolts with nuts
  • 1 - 4x6" piece of 1/8" plexiglass (usually can find a piece of scrap at a hardware store that they'll give you for free or $1)
  • GoPro sticky mount for flat surfaces
  • sturdy zip ties and a whole mess of little zip ties
Tools:  
  • Hacksaw
  • sandpaper 120 grit or so is fine
  • drill bits
  • drill


Building the Mount:

There are really 2 main parts to deal with.  The mount frame that is made from the carbon tubes and the camera platform which is from plexiglass.

The frame is made of two vertical tubes that will attach to the front lines of the kite.  There are two cross beams that provide torsional support for the camera platform and keep it from spinning and pointing somewhere you don't want it.

The Frame:


The Tee's should slide over the carbon tube, but just barely.  Position them about 4" apart on center with two on each downtube.   These don't need to be anchored unless for some reason they aren't tight.  Once connected to the cross-beams they aren't going to go anywhere.

Assemble both down tubes and then insert your cross beams.   Using a small drill bit, drill all the way through the Tee and the crossbeams so that you can insert a small brass bolt.  This will keep the cross beam from being able to pull out.  Normally if the length of the crossbeam is wider than where you place it on the lines, there will be a compression force on the crossbeam.  Better safe than sorry though.


Cut any excess bolt off past the nut.  This reduces the chance that steering lines can get caught on anything.

Regarding width of the crossbeams.  This depends on your kite setup and how far up the lines you want to fly the camera.  About 15-20ft seems to be a good distance.  Far enough that you can see a full fan of a cutback, but someone could still tell it is you.  Get some spare carbon tubes and just make different widths if you need to.  You will find that even full width, you can move it around a lot and the compression load is not a problem.

You will want to position the crossbeams about 1/3 up from one end of the downtubes.  This will be the "down" end of  mount when on the camera lines and will keep the ends of the tubes out of the camera field of view.  With adjustment, you'll be able to find the most stable position that doesn't show the tubing.

The Camera Platform:


Initially, I carved a little block of balsa wood that I had and used a bolt to a tripod mount.  It worked and was a great prototype.  Also offered some flotation had the system fallen apart and all my safeties failed.

For the second generation, I wanted more robust and simple.  Enter plexiglass.  Strong, cheap and a great mounting plate for a stick on GoPro mount.



Simply cut out a rectangle of plexiglass larger than the distance between your two crossbeams.  Mark and drill 4 sets of holes and zip tie it to the crossbeam.  Apply a stick-on GoPro mount and you're done.

I do recommend offsetting the mount towards the bottom of the platform to keep it from the view of the camera.

Connecting To Your Kite:

You have a few options for connecting to your kite.  Initially I used to thread my lines through the center of the tubes.  Depending on your kite setup, this may not be possible if the knots are too big.

Later and lazier, I realized I could just use three or four tiny zip ties on each down tube.  They each have a breaking strength of 30lbs or so and it's much faster than threading the lines.  Leave the ties loose enough to slight the frame up or down your lines until you get the right position.

Pro-Tips:


  • Use a safety leash.  Run a safety leash from your camera to around one of your lines.  Tape or zip tie it to the crossbeam so it doesn't flap.
  • For cutting through old zip ties that are on your expensive kite lines, use a piece of dental floss or other strong but small string.  Unwaxed is better.    Use it like a rope saw to melt through the zip tie.  Quick and won't leave you accidentally cutting your kite line with a knife or scissors.
  • Mark your kite lines once you find the sweet spot.
  • New WiFi enabled GoPros like the Hero3 make determining the best position easy.
  • Mount the camera on the "back" of the lines.  You can't really tell the difference after the shots are taken, but it allows you to land the kite and your camera will not be slammed into the sand or ground

General Experience:


It's been about a year since I actually set this up.  Usually I'm too pumped to get in the water and don't take a few minutes to rig the camera.  Be prepared for lots of disappointment.  I usually just take stills.  The video works great, but half of your shots are upside down and have to be flipped in software.

Stills come out great.  Previously the GoPro would take 1 shot every 2 seconds.  You would be amazed at how often the peak of action happens between those two seconds.  Newer firmware takes even more photos, so the time window for missed shots is smaller.  You'll still just barely miss a lot of great shots.

Water spots will also ruin your day. Such is life.  The good thing is that if you configure the camera to take a picture every .5 seconds and let it roll for your session, you may get something great.  Maybe not.  Every session ends up with a few good shots.

You will end up with thousands of shots to throw out.  It takes a lot of work to go through them.  Usually you can discard vast numbers with just a glance at the thumbnail.

Durability so far has been great.  Crashed kites haven't been a problem.  I have had the steering lines get caught on the camera once or twice, but it didn't affect the ability to control the kite.  I just returned to the beach, landed the kite and flicked the line free.  Can be done in the water as well if the catch isn't too bad.  Better still, just don't crash the kite.

Hope this helps someone.

Results from some old shoots.




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