‘Fly & forget’ KAP

I have been using a primitive AutoKAP setup to see if I can get good photos while concentrating on getting to know a new kite, an unfamiliar site or just want to enjoy the walk. You could call it lazy but there are times (‘light variable’ wind, up and down bluster)  when the concentration needed to get RC KAP working is beyond me.
When I get back to the KAP cave I have a pile of photos to sort through and the hit rate is always very poor. Just as the train was passing the camera was looking the wrong way, lots of shots that just miss something interesting on the ground etc etc. I have got the hang of setting the camera to behave and use a fast shutter/high ISO combination in ‘P’ mode so I get a good haul of sharp shots even if they are not of my fondly imagined target.
I have had some success in situations where nothing else would fly so I know there is merit in the method (or methodology if you are an archaeologist). By taking my time and using the ‘minds eye’ to place the camera where I think it should cover the target. I have managed to capture a huge radio tower:

a passing train:

and a fine bridge on its birthday:

The portrait aspect is fitting for these subjects but the missing nadir shots rob me of one of the best things about KAP: the ‘tumbling vertical’ or 3 point perspective view.
Good nadir shots are surprisingly tough to achieve and I use a hefty RCrig with video relay which works best with a second pair of hands on the camera control whilst the rig is carefully flown over the subject.
If the wind is kind I can work single handed:

…and the impact of the image is amplified by the foreshortening of verticals : pure KAP!
I might be expecting a bit much of a blind operated camera but there are 2 things I’d like to do with autoKAP to make it a bit easier to live with.
1. Speed up the step between shots. The basic click pan device won’t go faster than 3s and I have it geared really low so the steps between shots are tiny: it takes and age (2.5 mins) for the rig to complete a circle.
2. Get the tilt axis moving. The fixed tilt is limiting and if I need to change it I have to haul the rig down to do so. Getting those missing nadir shots would definitely get more from the vantage point the kite offers : why not look straight down from a great height?
I found David Wheeler’s blog on ‘RoboKAP‘ (a project which is a little way off production as yet) and relaisied this is what I need to do: use a controller to automate 3 servos and in no time I found the Gentles ClickPan Pro.
Mounted on my No.2 Brooxes rig the click Pan Pro controller gives me timer control of pointing the EosM through pan and tilt.
RoboKAP rig_2It is velcroed to the top plate on the left and its power supply is a 3.7v 100mAh Li-ion Nokkia phone battery taped to a Futaba connector. It’s not that light at 800g and I may opt for picavet suspension and IR shutter at a later date, this rig should have a gyro servo on the tilt axis but it was swapped out for another project a while back, hence the pendulum (gyro servos work best with a pendulum)  so you are looking at another parts bin lash up!
James Gentle supplied the board with a neat case marked with the connector numbers as holes in the case. A real time saver when wiring it in.
CPP_1Sockets 1 and 2 (1 at top) marked on the case. The control sequence is set with the dip-switches and the time interval by the blue dial.
CPP_2The minimum time interval is 1.3s which is, sadly, inside the pan step speed. I set it to 2 s which is as fast as I can sync the movements without overlap. This equates to 3 mins per circle but with 48 shots to the circle (as opposed to 12 in 2.5 mins with the previous set up) and nadir shots to boot I should get a great deal more out of each sweep.
First results are encouraging although positioning the rig to get the best of the blind nadir shots is much tougher than with a video down-link. On this flight the nadir position was entirely random. A few were well worth having:
My tilt servo is below par and not giving me the full 90, the shots to horizon are all tilted at 20 deg too low. Even so I got a good mix of shots:

I had a hard time keeping the rig aloft as the late afternoon air flow was dirty with thermal transfer. I was spooling line like a madman one minute and hanging onto a fierce pull the next. I failed to get a full 3 minute sweep from a single point in the sky- that will have to wait for smoother flow.
For a very modest outlay I have expanded the AutoKAP potential!


About billboyheritagesurvey

Heritage worker
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2 Responses to ‘Fly & forget’ KAP

  1. z1ggur4t says:

    Great video. I particularly like the economical patern. The Aurico puts the camera back at the horizon after every set of shots on the vertical axis. This just pans and keeps shooting, more of a sine wave than a saw tooth like the Aurico. Less time to complete a total 360 pass and start the next one. What is the maximum shot count for the vertical axis? You’re doing 3 here. The Aurico can shoot 4 from horizon to nadir.

    • So far I have only figured out the 3 step sequence in ‘out the box’ mode. There are more settings I can play with in ‘adjustment mode’:

      CPP Switch Table

      but I’m working through the ‘simple’ settings 1st, I don’t know how reversable the ‘adjustment mode’ settings are yet: I can’t see a re-set!

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