Trouble mocha tracking 196 frame shot

I have a shot that is hand held for 196 frames. There is some dramatic camera rotation in the Z-axis as the cameraman follows a person walking. I seem to get good tracks with the shapes I create. But, when it comes time to Solve, I get errors telling me that I need more layers or a different camera.

Any suggestions? Thanks in advance,

Comments

  • Triem23Triem23 Moderator

    How many layers are you tracking? Do you have at least two tracked layers on every frame? If one tracked element leaves frame partway through and another element enters frame, do you have overlap where both these elements are tracked for half a second or so? Are you tracking coplanar surfaces (one user had an issue when he was tracking a fence--he put two spline layers on the  same fence, and that's confusing to Mocha. He needed to delete one layer and use "Add spline to have both splines on a single layer).   What Solve model are you using? Are you using surfaces and grids to check your track? What looks like a good shape sometimes turns out to be not so great when checking with the grid (I was tracking a tiled roof the other day--shape looked good, grid revealed a "shimmer" from moire, and I had to shift the track to a window...).

    Mocha is often an art, not a science--it really depends on the shot and can be difficult to troubleshoot without seeing the footage. Sometimes you just have to track a different area, sometimes you have to actually NOT use a layer you've tracked (the shot with the tile roof was a problematic solve until I turned off the sky layer). 

    One concrete tip I can give is Mocha prefers a large spline and a small surface. Mocha also seems to track image sequences better than many video formats (mp4) 

  • So I will try to make sure each layer has a shape throughout the shot. 

    I have shaped the grids to take up a smaller area as suggested. 

    I'll try again and report back. 

  • Here is a link to the footage. Latest attempt resulted in a 97% solve before it failed. Maybe someone can make sense of how best to get a 3D track out of this.

    https://www.dropbox.com/s/uddosqocr1f2lro/_seq.zip?dl=0

  • Have you tried Autodesk Matchmover yet? It might work better for this

  • Does Matchmover export to Hitfilm Pro 2017?

  • HitFilm can import Maya .ma camera tracking files and that's one of Matchmover's export options.

  • Thanks! I will give that a go.

  • edited January 2017

    This is sort of what I was shooting for. The shot is very jittery, and Matchmover had a hard time tracking it. Thank god this isn't for a real world project. I would've shot it at a location with more ground detail around the person walking and jumping.

    https://youtu.be/hfUV6sb_X8Y

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