Page 1 of 2 12 LastLast

Thread: Overland Expo: Kite Aerial Photography

  1. #1
    Join Date
    Jul 2009
    Location
    San Diego, CA
    Posts
    1,100

    Default Overland Expo: Kite Aerial Photography

    Since a few people saw my kite photography rig flying at Overland Expo, and several more people have expressed interest since I posted one of the resulting photos, I thought I would post a thread to give as much info as possible about the rig and the theory behind it.



    First off, credit for inspiring me to undertake this goes to three entities, almost simultaneously: First, DesertBoater mentioned a friend who used a kit towed behind a boat used for overhead photography in a thread on UAV Photography. Second, Randal Munroe of XKCD fame (the best comic on the web, IMHO), as I found his early kite experiments while snooping his site, and MAKE Magazine, as they did a feature on their idea of a simple KAP rig around the same time. In my opinion, the MAKE magazine project was overly complicated and didn't reflect modern reality in terms of cheap and simple possibilities for kite photography, but I'd like to think that mine does.

    So, after a little research into "Kite Aerial Photography", or KAP, it turns out the "key" bit of technology needed for good photographs is the "Picavet Cross", or "Picavet Suspension", named for Frenchman Pierre Picavet who in 1912 described a rigging system that keeps the camera (relatively) level to the horizon despite changes in the kite string angle. Here is my simple rig:


    Just about everything I needed to make this rig I learned from KAPER e-zine, with this excellent introductory page. The excellent animation on that page will demonstrate exactly what the Picavet does for you, if it's not clear.

    For my use, I wanted to have the option of taking this rig along when I went hiking or backpacking, so I emphasized lightness and simplicity over everything else. I used some scrap carbon fiber strips I had lying around from my Battlebot days, added a couple screw eyes and some fishing line, and voila'.

    After you have the suspension, the next thing is the camera cradle. Many KAPers are really serious and have radio-controlled servo driven gimbal rigs that let them pan/tilt the camera while in flight. Mine is much more simple, just a pair of angle brackets from the hardware store with some carriage bolts and wing nuts, using what's referred to as the "LL Design" here. If it isn't obvious from the photo above, my rig is totally static, so to change the aim point I just walk down the kite line, re-aim, and release again. It turns out I don't have to fly very high to get great photos, so this isn't tedious at all.

    The last bit of "tech" for the KAP rig, and possibly the only area I have added anything "new", is the shutter release system. This is where I felt the MAKE Magazine build got WAAAAY too complicated, using a mechanical shutter release based on a wound rubber band dampened with silly putty, if I remember correctly.

    Instead, I've basically turned a $40 Canon SD450 P&S I got from Craigslist into a time-lapse shooting camera and just let it fly and shoot, then sort out the pictures later. They key is a Canon camera running the Canon Hack Developers Kit (CHDK). This sounds ominous and complicated but basically you just select the correct image for your model of camera, load it onto the SD card, boot the camera, and off you go. In my case, I'm running a user-written script called "Ultra Intervalometer" which is basically a very customizable soft-intervalometer (camera speak for shooting on intervals). I set the initial delay, set the inter-photo delay, and then when I'm ready to fly I just hit the shutter release button once and let her fly. Incidentally, using CHDK also lets me capture images in RAW format, something which this older P&S doesn't normally do.

    Now I've got a rig, but I still need something to fly it from. My best KAP kite so far is this basic 14 sq ft sled kite I got from my local tourist kite shop. It's a self-inflating sled with no rigid structure, and it all folds up into the storage bag that acts as the drogue/tail - about 14" by 6", collapsed. This kite is super easy to launch solo, even in mild wind, and is fairly stable even in high wind. More importantly, it has WAY more than enough line pull to lift my rig (about 12oz, w/ camera, if I remember correctly). I could probably get fancy with an RC rig with this kite, but I like the simplicity. If you ever want to make another Dad look bad in front of his kid, show up with this kite at a park on a breezy day when he's trying to launch one of those cheap Disney-branded diamond kites you get at the drug store. While he runs backwards trying to get enough lift under the kite to get it into the breeze, you unpack the sled, clip it to the kite line, give it one good tug and.... UP! (Remember to wear gloves, this kite has some serious pull)

    Here's one more example of the results I got with the rig:


    As a bonus, due to a happy accident, during my first flight at OvEx11 I accidentally bumped the camera into "video" mode. The intervalometer was still running, so it was shooting a series of short movies as it triggered the release over and over. I stitched these back into a single video so you can sort of get a camera-eye view of me bringing the kite down to make aim adjustments. You can also see the BEST feature of a rig like this - it attracts attention, especially from children, whenever you fly it:

    Last edited by Herbie; 03-28-2012 at 08:33 PM. Reason: Fixed video link
    Herbie - K6ZMB
    "My minivan is cooler than your bro-truck"
    2003 Chevrolet Astrolander 4WD Van - DIY GTRV PopTop, 4" Lift
    2002 Subaru Impreza WRX "Outback" - a.k.a Frankenstein's Trailhead Vehicle. Lifted, WRX-TR Brakes, STi Seats + More

  2. #2
    Join Date
    Apr 2009
    Location
    Eugene, OR. USA
    Posts
    1,834
    Hey thanks....you've got me interested now....I'll have to try this later this spring!

  3. #3
    Join Date
    Jan 2007
    Location
    Prescott, Az
    Posts
    3,816
    Very cool Herbie. Thanks for sharing the details. Looks like a lot of fun.

    Someone else here was going after setting up a high end remote helicopter with a DSLR camera. I would hate to crash that puppy!
    Brad

    My Photo Gallery


    2004 4Runner - 2011 Kimberley Karavan

  4. #4
    Join Date
    Dec 2008
    Location
    DFW
    Posts
    3,283
    Quote Originally Posted by Tucson T4R View Post
    Very cool Herbie. Thanks for sharing the details. Looks like a lot of fun.

    Someone else here was going after setting up a high end remote helicopter with a DSLR camera. I would hate to crash that puppy!
    Lol. I remember that thread.

    Thanks for sharing, Herbie. Do you think anyone would take issue to me borrowing the idea for some of our pics this year?
    Get out and make nowhere your special somewhere!


  5. #5
    Join Date
    Oct 2009
    Location
    Saint Louis, Missouri, USA
    Posts
    1,096
    Neat. Thanks for posting.

    x2 on CHDK.

  6. #6
    Join Date
    Jul 2009
    Location
    San Diego, CA
    Posts
    1,100
    Quote Originally Posted by Mr. Leary View Post
    Lol. I remember that thread.

    Thanks for sharing, Herbie. Do you think anyone would take issue to me borrowing the idea for some of our pics this year?
    You mean building your own rig to take pictures of your events? Heck no, as far as I can tell the whole KAP community is all about sharing info to get others into it. I've found even with a "low" flight of 25-50 ft, you get photos from such a completely different perspective that they're almost always interesting. It's great for capturing the "scale" of big group activities, as you can see in my above shots. I can't wait to shoot the next SoCal expo group meet & greet. In short: Do it, but be sure to post the results!

    One other thing I forgot to mention in my first post:

    Some folks (including that Picavet Basics page I linked) build a little "carrier" so they can store the picavet suspension once it's all rigged up. I can never keep mine from getting tangled, and having it rigged detracts from the ability to collapse it and make it small, so I went a different direction: You can see in the photo that there are some small labels at the corners and a big label on one side: That's basically a cheat-sheet for the rigging order. I keep a small spool of fishing line, the two line-trees (bent coat hangers to attach to the kite line), the center ring, and a carabiner or two (for holding the rigging up on stuff while I get setup) in a ziplock bag and just rig the line on-site. It only takes a couple of minutes.

    If I'm flying from multiple locations on the same day, or know I'll be using things again soon, I just clip a carabiner into one end-ring and hang it on the T-end and slip the other end-ring over the point of the massive 14" sand-stake that I usually use to anchor the rig: (I DID mention that my sled has a lot of line pull right? This stake is barely adequate)



    At least that way I can carry things around, it's just not really adequate for long-term storage as things can get tangled unless the cross is always hanging down.
    Herbie - K6ZMB
    "My minivan is cooler than your bro-truck"
    2003 Chevrolet Astrolander 4WD Van - DIY GTRV PopTop, 4" Lift
    2002 Subaru Impreza WRX "Outback" - a.k.a Frankenstein's Trailhead Vehicle. Lifted, WRX-TR Brakes, STi Seats + More

  7. #7
    Join Date
    Nov 2005
    Location
    Salt Lake City, Utah
    Posts
    1,787
    Wow, that is a really cool rig. CHDK is the most under-rated thing on the planet. You can make your really pretty crappy Canon p&s camera do magical things. Have you gotten yours to shoot RAW yet?

    Nice job and thanks for sharing!
    Michael Slade

  8. #8
    Join Date
    Oct 2010
    Posts
    895
    Quote Originally Posted by Tucson T4R View Post
    Someone else here was going after setting up a high end remote helicopter with a DSLR camera. I would hate to crash that puppy!
    You might be talking about me?

    I'm working on it, but not the DSLR yet. Just a P&S and a ContourHD.

    Some guys have crashed DSLR's and they are surprisingly durable. One guy buried it 6" in the dirt, and it still worked after some minor repairs.

  9. #9
    Join Date
    Jul 2009
    Location
    San Diego, CA
    Posts
    1,100
    Quote Originally Posted by Michael Slade View Post
    CHDK is the most under-rated thing on the planet. You can make your really pretty crappy Canon p&s camera do magical things. Have you gotten yours to shoot RAW yet?
    I agree, it's enough to keep me coming back to buying Canons in the SD line, anyhow.

    Yes, I have RAW versions of all the photos I shot from the kite, it's just a checkbox in the menu!

    I know some of the guys doing serious time-lapse stuff also take advantage of being able to manually set aperture, shutter speed, etc. so that they get consistent exposure shot to shot, which makes a big difference in having your time-lapse not "flicker". That's the kind of stuff you just normally can't achieve until you get to pro-sumer level equipment, so it's awesome to have it in just a small/lightweight package.
    Herbie - K6ZMB
    "My minivan is cooler than your bro-truck"
    2003 Chevrolet Astrolander 4WD Van - DIY GTRV PopTop, 4" Lift
    2002 Subaru Impreza WRX "Outback" - a.k.a Frankenstein's Trailhead Vehicle. Lifted, WRX-TR Brakes, STi Seats + More

  10. #10
    Join Date
    Jan 2007
    Location
    Prescott, Az
    Posts
    3,816
    Quote Originally Posted by Paladin View Post
    You might be talking about me?

    I'm working on it, but not the DSLR yet. Just a P&S and a ContourHD.

    Some guys have crashed DSLR's and they are surprisingly durable. One guy buried it 6" in the dirt, and it still worked after some minor repairs.
    Yep that be you.

    I for one am looking forward to your experience once you get airborne and start shooting. Looks like a crazy fun hobby (or potential business) on either the Heli or Kite platforms.

    Heck, just flying the RC helicopters without the camera would be a kick.
    Brad

    My Photo Gallery


    2004 4Runner - 2011 Kimberley Karavan

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •