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Back In The Air

Posted by Tom Benedict on 07/02/2012

I’m back in the air!

A couple of weeks ago I got my statement from Getty Images. I’d sold another kite aerial photograph of Hawaii. I told my wife, and from there we got into a discussion of photography in general and the mental roadblock I’ve been trying to work through. It was a really good conversation. She did more than her fair share of verbally kicking me in the butt to get me off top-dead-center. Her closing argument was that KAP gave me a unique perspective on a unique place, and that obviously someone was willing to pay money for it. Her final statement: Get your KAP gear back together and get back in the air.

So I did. I really did get all my gear back into my KAP bag. But for the past two weeks the weather has been anything but cooperative. When there was wind, I couldn’t fly. And when I could fly, there was no wind. Or there was rain. Or gusts. Or something! It was driving me nuts. I tried again last Saturday. One location was like a sand blaster, and less than half a mile away it was dead calm. I griped. I groaned. But no way was I putting my camera up in that. Sunday I wrote a post about trying to get back into KAP, and how uncooperative the weather has been. But I didn’t post it. Somehow it just seemed too whiny and unproductive.

Yesterday I brought all my stuff in to work on the off-chance I’d have wind during lunch. It wasn’t great, but it was more than I’d had in over a month. I gave it a try.

Winds were blowing kona (the opposite of the normal trade-winds), and I’d made some changes in my gear, so I went to a favorite gear testing spot. It’s not the most photogenic place on the island. Not by a long-shot. But it’s open, it’s grassy, and when the wind blows from the right quarter the nearest power lines are a good distance away.

The big change in my gear is that I’m flying with a video down-link.

5.8GHz KAP Gear

This is a first for me, and a big departure from how I’ve done KAP in the past. I’ve always been a predominantly RC-KAP kind of guy, but I’ve always done blind aiming, where I look at the camera and guesstimate what it’s pointing at. I’ve become reasonably good at it, but it’s not an exact science. I’ve missed my fair share of good photos this way, simply because the compositions I got didn’t give me enough to work from. This lunchtime test session was the first time I’ve had a viewfinder to work with.

Before getting into how I liked doing video-assisted KAP, this is the entire 25-shot contact sheet from the flight:

VKAP Session 1

Already this bears almost no resemblance to any previous KAP flight. For starters, there are far fewer photos. Next, a higher percentage of them are workable. Next, only one is unacceptably blurry. All in all, the flight went well! Here are some specific photos I worked up:

Second VKAP Photo

This was the second photo of the session. Except for RAW processing, it’s exactly how it came off the camera. Normally I aim blind from the ground and make several photos as the camera wozzles around in the air. This gives me a pepper-shot style selection to choose from. After the flight when I’m processing the photos, I’ll pick the one with the closest composition to what I had in mind and work the photo from there. In this case the composition was right from the get-go. No rotation or cropping was done on this after the fact. The building behind me provided the rooftop I photographed as an abstract during WWKW 2011.

Kahilui Theater

A nearby landmark is the Kahilu Theater. I’ve photographed this on several occasions from my earliest days of KAP. I’ve probably exposed over a thousand frames of this building, but only a handful turned out to be useful. Often the cropping necessary to get a decent composition trimmed away too much of the frame for it to be usable. In this case the base composition was right off the camera. Unlike the previous photo I did some more work on this one. In addition to RAW processing I rotated the photograph to flatten the horizon, and applied vertical perspective control tilt to get my verticals vertical. The horizontals were left as-is since no effort was made to line up on the front of the building. Yes, you can do architectural photography from a kite.

That Damn Tree

That damn tree!

This tree has been another repeat subject during testing. I still haven’t photographed it in a way that I’m happy with, but this came awfully close. Except for RAW processing, this is straight off the camera. No cropping, no rotation, no nothing.

Fly This!

This was the last frame from the session, just to verify everything was working. (But I kind of like the whole Billy Idol fist-at-the-camera thing! Even if I’m not wearing gloves and have a winder dangling from my pinkie. I’m still channeling Billy here!)

So how did this all work? Surprisingly well!

I did have one scary moment when I was composing a photograph of the town and grass suddenly grew up from the bottom of the frame! I looked up and saw my camera had landed on the ground. Clearly this is better done as a tandem team the way Fanny and Anthony work, or in more solid wind where the camera will stay in the air where it belongs. But hey, that’s why I do my testing where the grass is soft and the rocks are scarce.

My method, in practice, was:

  • Set the camera to shutter priority, 1/2000 sec. (This was not always achievable because of lighting conditions, unfortunately.) Single shot, daylight white balance, ISO 100.
  • Install the camera in the KAP rig – plug in the Gent-FOCUS shutter release cable and the video down-link cable.
  • Power up the camera, rig, and video transmitter and turn on Live View on the camera.
  • Launch the rig.

One step I didn’t do during this flight was to set my focus/exposure point to the center of the frame. It was way off to one side because of some ground photography I’d done earlier in the morning. I didn’t even think to check until the camera was a hundred feet away! But I was still able to do decent KAP.

Once the camera was in the air and in a good location to photograph the subject, my practice was:

  • When the camera is in position, rough-compose the image.
  • Flip the shutter switch forward (equates to a half-press on the camera’s shutter button).
  • Wait for focus lock (focus rectangle goes green).
  • Final-compose the image and wait for the camera motion to settle.
  • Flip the shutter switch backward (equates to a full-press / release on the camera’s shutter button).
  • Repeat…

I’m still not smooth with the new gear, but I think I’m to the point where I can use it somewhere that’s a little more photogenic. One future change I’d like to make is to add a remote relay that’s tied to an unused channel on my radio to power the video transmitter on and off remotely. Along with this, I’d like a second switch to power the video receiver and monitor on my ground radio as well. I find I spend a lot of time positioning the camera in the air by eye before I ever look at the video monitor. If I could turn off all the video gear and only turn it on to compose the photograph, it would save on batteries and make for longer flights.

– Tom

P.S. There’s a second change I’d like to make: The video reception is noisy. I’d like to swap out the stock antennas for a pair of cloverleaf circular-polarized antennas. Project for another day.

3 Responses to “Back In The Air”

  1. There you go! Easy. Now you have a choice of methods- shoot what you see and when you want to relax revert to AutoKAP! One thing I find with using the down-link is that it can get stressful if the kite is misbehaving and you can’t take your eye off the screen for fear of missing that magic shot. Great results for a first time out too, you have done the right thing by working your way into it too, nothing like over-ambition to make things more difficult than they need be..but hey! wear some gloves man!

  2. Tom Benedict said

    Hahaha! I’ll wear gloves next time. For sure. When I put everything back in my KAP bag, my gloves and hat were the first things I re-packed. BEFORE the rig.

    I need to get more sessions under my belt before I try this anywhere really challenging. I’m still a little shaken by seeing the grass come up during that one shot. It’s easy to get disoriented.

    I’ve got some changes I want to make to the setup. I think I mentioned the extra switch on the ground unit and the relay switch on the rig for powering the video gear on and off. (Even better if I rig the ground switch to power on the receiver and monitor, AND trigger the remote relay!)

    Another is to swap out the video antennas for cloverleaf antennas. I’m getting some glitching in the video signal that could be interference. Cloverleaf antennas are circularly polarized, so that should help. They also have a modest gain, which can’t hurt either.

    I’m also leaning toward that LiPoly battery pack you showed me for the ground radio. I think adding the switch and relay will give me some increased battery life, but I wouldn’t mind adding extra capacity as well.

    Eventually I think I’ll want a larger screen, too. Gaaaah! The list just goes on and on and on.

  3. Tom Benedict said

    I ordered a bunch of stuff from Pololu Robotics to let me play with power distribution. I also have a DPDT toggle switch at home I can stick in my ground radio in place of one of its SPDT switches. So the plan is:
    – Use the DPDT switch on the RC transmitter to power the ground-side video gear off of one set of contacts, and send a full-throw signal on one of the RC channels with the other. Throwing the switch does both simultaneously.
    – A relay switch on the KAP rig read the RC channel the DPDT switch is wired into in the RC transmitter, and uses it to switch power to the video transmitter on the KAP rig.
    – I picked up a 9.5V DC boost converter to play with in an effort to get rid of that 9V alkaline battery I have strapped to my rig. I don’t know if I’ll stick with this long term, but I like to play.
    – I’m probably going to add a line filter to the power going to the video transmitter. I expect adding all this stuff will make things noisy!

    The cloverleaf antennas will have to wait until I can get some RP-SMA M connectors to play with. Hm… Maybe time to go scrounging in the e-waste bins at work!

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