Best way to plan a shot you are going to track in Hitfilm Express

DarrynGlass
DarrynGlass Website User Posts: 49

I am playing with tracking for the 1st time and the footage (not mine) I am using does not have any really good tracking locations to use (nothing really distinct).  I am wondering how others have handled this.  Do you put brightly colored tape on something when you know you are wanting to track the scene?  Or I have seen little LED tracking lights also.  Interested in thoughts.

 

Comments

  • Palacono
    Palacono Website User, HitFilm Beta Tester Posts: 3,422 Enthusiast

    Play with the Methods and Options available in the tracking tab. There is rarely something that can't be tracked without the need for markers before you start worrying about how you are going to remove any markers you put in your scene.

    I've managed to track and replace a sky that was mostly grey with very slightly darker and lighter grey sections in it that the Optical flow method decided was all too similar to track; however the Template Match method worked just fine with one of its Options selected .

  • Triem23
    Triem23 Moderator Moderator, Website User, Ambassador, Imerge Beta Tester, HitFilm Beta Tester Posts: 19,791 Ambassador

    There is an advantage to tracking markers - you have a controlled, high contrast marker to lock on to. There is a disadvantage to tracking markers - a lot of work to get rid of the silly things, clone stamping, patching, roto work around any thing crossing your patches....

    Like Palacono says, playing with some of the other options in tracking can help. Optical Flow kind of looks at pixel motion, and can be better at tracking in some situations, like if the object is moving closer or farther away. Template Match looks for a match of the tracked pixels and can be better with pans and sideways motion.

    There are other things to try too, like tracking in a specific channel or upping the iterations of the tracker. The manual for the most recent Hitfilm Express doesn't seem to be up yet, but the process is the same in Hitfilm Pro, so, here's that manual: http://fxhome.com/reference-manuals/hitfilm-pro

    Other things to think about when planning a tracking shot include camera motion. Hitfilm's tracker is a POINT tracker which means it's looking for a specific point. Fast camera movement - motion blur - is a great way to confuse a point based tracker. Even without blur (maybe shooting at a high shutter speed), the green box in the tracker shows where Hitfilm is going to look on the next frame. If the point moves outside the green box, Hitfilm lost track of it. Fortunately you can change the size of the green box and enlarge the search area.