Tracking a tilt and pan camera shot

Hi, everyone.

Just got a new system that was capable of running Hitfilm and I am using the eval copy until I can get a little profficent at it.  I have some old project footage from a number of years ago that I had thought to put into it a 3D model of a dragon or the Jupiter 2 flying overhead then landing in a field.  The camera was on a tripod but I panned and tilted up to follow it across an empty sky; now I am trying to figure out if it's possible to using point of planar tracking in this shot for adding the 3D.  It isn't very smooth and fluid.

What are the size and format requirements to attach the clip?

Comments

  • FxHome's servers have limited space for user attachements--I'd recommend uploading to Youtube and linking here, or uploading to Dropbox/Google Box/iCloud and attaching a download link.

    That said--if it's an empty shy it might be untrackable: Mocha's planer tracker looks at areas of pixel texture to track and generate a camera. If your sky is a REALLY empty sky--cloudless, and nothing like a tree or building poking into from from ground level--then Mocha can't track it. There won't be any detail for Mocha to look at. This applies to a point tracker as well--the tracker needs something to look at, and all-blue sky doesn't have reference.

    Obviously the parts of the clip that have your field will have nice texture to track--at worst, you track part of the shot, but do a sky replacement, the just full-CG the motion for the parts lacking ground.

    If you have some clouds to track, you could be in business. We'll see once you get the clip online. :-)

  • Thanks, Triem23 for responding.  I was caught in a huge Comcast outage for 24 hrs and I apologize for not responding quicker.  If I have done this correctly, here is a link to the video:

    https://drive.google.com/file/d/0B01ci7dc2fYVT1g4b0RFbktqTm8/edit?usp=sharing

    It's not a blue sky; overall kind of gray and only a few clouds so I suspect it is not suitable for tracking.  I had thought about the option of CG for the sky but I wanted to try this first if it was possible.

    Thank you very much for the input.

     

     

  • To me, there seems to be enough texture in the clouds for Mocha to track it. Since it was shot on a tripod, the one plane should be ok.

  • Thank you, rgbii, for replying.  I am happy that my upload worked and was viewable.  I had been trying to track it with point tracking and not planar.  I will have a go at that now.  One question, since I am extremely new to this:  Should I orient the plane vertically from top to bottom or horizontially along the ground?

  • If using Mocha, I would set the tracking area for the top half of the frame and unlink it, so you don't have to keep moving it as the camera moves.

  • @tddavis--I'm going to link to this other recent thread with some mocha questions, simply because I left links in there to several tutorials on Mocha that might help you answer your questions... And I'm too lazy to scour the internet for those links again. ;-)

    http://hitfilm.com/forum/discussion/5633/looking-for-background-tracking-and-replacement#latest

    I agree with rgbii--I think you have enough cloud texture to track in mocha. Here's a quick mocha hint that I don't think comes up in the tutorials I've linked:

    When you go into mocha hitfilm, above, and to the right of the preview window showing the footage you're tracking there's a button that looks a bit like a cog or an asterisk (*) There will be a field next to this button that will have the value of 1.0 in it. This is a "Brightness Scaling" function--if you click the * button, this will activate the function--if you set the number value to higher than 1 mocha will brighten your footage before looking for texture. If you set the value to less than 1, mocha will darken your footage before tracking (note, this won't change the actual footage--just how mocha looks at it.) I find when tracking skies it's often useful to set brightness scaling between 0.7 and 0.8, which will darken the shadows of the clouds and make it easier for mocha to  see the cloud texture.

  • Thank you so much,  Triem23.  I am watching those now trying to  learn how to do that.  I did find the button  to adjust the lightness like you described and attempted it but I didn't lock the track area to the frame correctly, I guess because it followed the objects at the start.  So I am researching those videos for tips, but I have made some progress.

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