Green screen tracking with 3d tracker - Help needed

This works great for wide shots on green screens.
BUT - how do I do close ups? (The close ups has wall trackers and mic stands boom arms with red dots)

Anyway to force trackers to points (rather then auto select) and force a lower number of track points?
Or I need to go out to Mocha Pro - and then come back?

Thanks

Hello,
I presume you're talking about the 3D camera tracker, right?

The camera tracker allows a mask input. "Auto" tracking points are only added within this mask area. So for example, mask around your actors,invert the mask, connect it to the camera tracker and now it will only add points outside your masked area.

Tick the "Preview AutoTrack Locations" in the "track" tab and fiddle with the detection threshold and minimum feature separation to change the number of tracks added.

Using the camera tracker is an iterative process where you track, review results, delete wayward trackers and repeat. So don't worry about extra trackers at the start. You'll clean them as you go.

DC

Great- thanks - yes 3d tracker

Here is an example image

greenscreen1.png (89.18 KiB) Viewed 1590 times

- there are not enough 3d points for fusion - but 3d tracking works in Mocha or Nuke because we can define very set points in each dimension - and we have the mic boom to define parallax in Close Ups - like we can do it with 11 points in total...

I am Ok on the garbage mattes etc.

Is there a way to track these close ups on greenscreen in Fusion?

thanks

If you are successfully tracking the same part of the same shot in another tracker, then perhaps send the shot into Blackmagic support for their devs to refine their algorithms. I guess that it is not detecting enough parallax between the two planes you have defined in the shot to solve the 3D move. With two planes, a small camera move with a wide angle lens would solve just as correctly as a large camera move from further away with a zoom lens, because the angle of change between the planes could be the same in both circumstances. The only way to get accuracy would be to either perfectly specify the lens and backplate size (which you can do in Fusion) or specify the distance between the two planes at every tracked point (which afaik you can't do in Fusion).

DC

if you could just add manual tracks that would be so satisfying

There are some situations where manually placing trackers is helpful - such as having a tracker that sits exactly where you plan on inserting a 3D object later. But if the issue is not enough 3D spread to uniquely calculate the camera move, then manually placing trackers won't help alone. You would also have to be able to enter the real world coordinates of each tracker.

Remember this is a user-to-user forum, so be sure to raise your suggestion directly with BM as they might not pick it up from here

DC

Hi there,

Very interesting topic indeed, thought I'd go through Mocha Pro's Camera 3D Solver (inside fusion with ofx or in standalone if the 1st is too slow).