More points = better tracking accuracy? Myth or fact?

I’ve been told by a VFX lead in my studio that while tracking, the more points you can put down around your tracking spline the more accurate your track will be. But I can’t find that tip confirmed anywhere else around the internet, or the manual. Has anyone heard this before? Is this a real thing?

Definitely a MYTH! Myth Busted! That is something I have heard before but it is 100% incorrect. :wink:

To get a more accurate track, either track MORE pixels by using a larger shape on the same planar area or grab similarly moving planes with add to X-Spline tools. Or simply increase the percentage of pixels tracked value up to 100%

You can also increase your track search area in the track tab so the track algorithm looks in a larger area for the texture you are tracking, or you can increase the angle and zoom for search areas all in the track tab on the righthand side if your object is rotating or zooming rapidly.

All of these options do slow down the tracking time, but will increase accuracy.

Please correct your VFX lead so they can track properly in the future, there’s a lot of superstition I have seen around “what works better in Mocha” but you can always check our documentation to separate the delicious wheat from the disinformation chaff. :wink:

Cheers,
Mary

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Whoa! Mary P! I never thought I’d hear it straight from you.
Thank you kindly for clearing that up. I had always wondered why I had been told that, especially since I’d never seen you doing that before in any of your videos, while still getting an excellent track.
Cheers-

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Happy to help! People also believe sports jerseys are lucky if you don’t wash them. I can not speak officially to the accuracy of that superstition, but hey, folks all have their little rituals. This adding more points “ritual,” however, simply doesn’t work… making the spline larger absolutely does. Also, sometimes making the spline go a few pixels outside the edge of the object you’re tracking can help too. Maybe that’s how the rumor got started?

classic!

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Just to add some seeds to this Facts Bread we’re baking:

  • Drawing the shape outside the object boundaries is the best solution to a good track unless the background is more detailed and contrasted that the thing you’re tracking. In this case, it’s better to do the opposite and track inside the edge of the object.
  • Moving the surface doesn’t alter the underlying tracking information unless you’re using Manual Track
  • Moving the spline doesn’t affect anything other than your search area. Tracking is not adjusted by adjusting the spline (this is a common misunderstanding)
  • Don’t track in Mocha while operating heavy machinery.
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Excellent tip for new cooks Martin. I wish I had realised that approach sooner than I did!

Based on the advice in this post, I tried the approach on a handheld shot (Sony FDR-AX100 - 4K) of an A380 about 7 kms after taking off from Nice airport as it passed by the city’s beachfront promenade. The points created for tracking in Mocha Pro 2019 were just on or near the outer points of the aircraft (i.e. wingtips, nose, tail and the like). Background to the aircraft was blue sky with some whispy white clouds. The result from Mocha Pro was extraordinary - I couldn’t be happier. I did a few runs with different settings, but the final result was unexpectedly stunning with only a little bit of ‘jello’ on the engines, especially when considering it was a handheld shot of an object possibly 1 -2 kms away. Impressive!

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And you can fix any problems with Adjust Track!

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