Tracking drone footage

edited September 2016 in Everything Else

Hi guys,

Well I've joined the drone revolution so expect a spate of boring aerial videos soon

Can mocha track a drone shot flying over trees.

Is there anything to bear in mind while shooting 

Thanks

Comments

  • I've tracked aerial footage before. Sometimes easily, sometimes, not so easily. With Mocha it all depends on having something flattish to lock on to. 

    In general take a look here to make sure you're legal. 

    http://hitfilm.com/forum/discussion/40804/live-in-the-usa-own-a-drone-you-should-look-at-this#latest

    Start slow on a calm day. Don't go low until you know what the hell you're doing. Do NOT fly that thing within 20 feet of anyone until you REALLY know what you're doing. Last week I was event video for a music festival. A videographer who had never flown that drone before decided to fly, at night, in gusty wind, 5 feet over a concert crowd. The idiot flew his drone into the face of Krayzie Thug of Bone Thugs n Harmony. Krayzie left in an ambulance. 

    No, I don't have footage. I'd have uploaded it already. 

    The key thing is a drone can be dangerous. I've seen drone operators crash on an active racetrack causing multi vehicle pike up and injury. Last year firefighting aircraft were called off from a rather large fire right by my residence because drone ops were in the flight path. There's a reason for FAA regulations. Just... Don't be an idiot. 

  • Hi @Triem23,

    As always first to reply.  I'm already well aware of the CAA rules here in the UK and 20ft from a person is pretty much against the rules. 

    I'm  actually quite sensible.  I've no intention of trying anything clever for a while till I get used to the thing and have a decent few hours simple flying behind me. Thanks for the tips though. I've seen some on you tube that would do well to read them for sure.

    As for flat surfaces. It was going to be over mature trees and then into an open space. Might a point tracker be better. I have one

  • Depends on the trees, I think. Of you have a thick canopy, then there are probably things you can tell mocha are planes. Sparse vegetation and all the trunks become spikey. 

    Oh, Mocha--since it's looking for flat--can have issues with extreme wide lenses. Also I have found mocha like image sequences more than mp4. I think a good dose of Action Cam undistort of fisheye warp to smooth out lens distortion, then rendered as a png sequence for mocha will help. I haven't found it yet, but there's a Simon Jones tutorial where he discussed undistorting footage to add VFX, then redistorting to get the original look back. 

     

  • Mocha can work, it depends on what you want to do with the shot.

    I used it to patch a dead patch on a lawn on a property flyover video.

  • Thanks again @Triem23 and @Palacono

    The shot will have 3d aircraft composited in flying over the canopy. At the moment it's still reasonably thick as I have woodland near my home now I've moved house 

  • edited September 2016

    I got an interesting tidbit while watching a Mocha tutorial. Something that is truly flat is ideal but you can use something that is effectively flat in relation to the camera and its movement. The TUT was in an alley and they tracked the end of the alley. The stuff past the alley was not flat but with the distance from the camera, lens in use and camera movement, it was effectively relatively flat enough to get a decent camera solve.

  • Hi  NormanPCN

    I think I know the one you mean.

    I'll go check it out again as it's been a while 

  • Triem23Triem23 Moderator
    edited September 2016

    @NormanPCN yes, you said it better, but I think I can refine even more.

    With Mocha you're looking for areas which dont parallax much. So, you can easily track, say a torso, even though it's curved because it doesn't have much apparent parallax. 

    So...Trees. If you're relatively high, the bulges and curves of different branches will flatten out enough to be "planes," whereas, if you're low over treetops you'll get every little curve, causing issues. 

    Since you want to add airplanes, I'll assume you'll be a couple of hundred feet up, at least, in which case things should flatten. 

    Of course mocha needs (at least) two non coplanar surfaces to solve, so some sky texture is useful. Shooting straight down becomes a 2D track. 

    And if you have a point tracker, that's an option. 

  • If warpping is messing up the track, dewarp the footage then track it. Once you have the track apply it to the text and you can delete the dewarp feature that was on the shot. Then I think you can apply a bulge to the text and inverse it. This should make it look pretty uniform.

    Sorry in advance if I misunderstood what you were trying to acheive.

  • Thanks for all the information everyone. I was looking for the aircraft to be kind of skimming the treetops. So the drone moving horizontally and the camera pointing  out to the right or left at 90 degs to the direction of travel but also horizontal not looking straight down. However now @Triem23 that you mention straight down I could cut a shot like that in as well. Either way it's a travelling shot and it would end after the aircraft leave the treeline so I assume long pan techniques apply. Disconnecting the spline from the footage in mocha.

  • Triem23Triem23 Moderator

    Given that the trees will be different heights, I would try one for the sky, and maybe multiple tree splines? One in the distance for midground with a disconnected spline, maybe several in FG that are allowed to move in and out of frame? 

    Mocha often  requires experimentation after the footage is shot. 

  • Yeah I get the feeling this may well be a "learning experience " in both drone flying and mocha. 

    @Triem23 aren't you in the states? Don't you ever sleep?

  • Triem23Triem23 Moderator

    I'm in the states, and I tend to work nights, so I have strange hours. 

  • Ah I see. Well you surely are a seriously helpful guy. Thanks for all the help buddy and to everyone else on here.

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