TJPARSONS explores practical applications of motion tracking and simulates a Zombie bite.

So why is this under the "No Budget Film Tools" section you might ask? What about the Adobe software? What about the Mocha for After Effects that you will be using? Well I'm assuming that if you are truly serious, you have invested the bare minimum(seen below). Digital effects can sometimes be a godsend. They involve less materials and typically only involve some pictures, animations, time and imagination. Rest assured I love both practical (in camera) effects and digital effects equally. There are times when one may be effective than another; sometimes one adds to another (they can be composited together). Its up to you as a filmmaker to discern what's best for a specific shot in your production. But motion tracking, to an independent filmmaker,  opens up a lot of doors that were unreachable just a few years ago.

MOTION TRACKING: Teaching Demo 1A-009-G

If you just happen to want to try digital effects (those done in computer) instead of practical effects (ones that are made and achieved in camera or the physical world) or a combination (my passion) and you have a sufficient knowledge of animation; I would suggest motion tracking.

This will not be a tutorial about how to program motion paths for your movie or film (I've seen many other tutorials that are way better- ones that I use myself) but this may just open you up  to the possibilities and applications beyond the demo shown.

Motion tracking is a way to track your subject on screen and by using 2D or 3D animation composite them as one image;  so they seem as part of the same in camera shot.

Mocha tracks the subject frame by frame , and by making a  set of points will bond with the subject moving as the camera moves and moving as the subject moves .

This can be quite cost effective because you are saving yourself materials from actually building what is needed for the shot with raw materials or having to destroy something that already exists. If it needs to move with the subject and the camera and seem impossible to do with makeup chances are, motion tracking may be one of the best options.

If the camera shakes during a running or action sequence, it does not matter as long as the points on the subject have been defined by Mocha (right vs. left -pictured above), it will move with the subject and the camera shake. Utterly amazing, eh?

What you are looking at here is a very simple motion tracking demo of a Zombie bite in the chest. No color correction has been added; no shadows or blending have been added either. This is just a simple 3 layer animation made from pictures of meat animated in a fluid motion to simulate muscle and sinew movement around a breastplate.

The animation is a composite of a layer of skin with a hole, followed by layer underneath (animated in real time) followed by what I call the bone layer or base layer. After that small oval of muscle and gore is animated. I track the subject (me) with a green oval on my chest. You can track on anything as long as it is noticeable on every angle on camera.

If tracking on bare skin you can use tape, magic markers or ink pen. If you are tracking a landscape or sign just make sure your points are tracked on a definable edge or mark. As the program searches through the footage it takes into consideration every movement of that point in every frame, and the end result is a composition that combines elements to add extension or augmentation to the subject.

It that seems as if I am barely moving at all in this clip, but I assure you that I had to make make several passes and adjustments to ensure that the animation moved with my body. If it was any amount off, as it was initially, it just looked like the animation was floating around on its own- detached from my chest. Sometimes you may need to adjust manually as the computer processes the footage frame by frame. Then when you add shadows, color correction and atmosphere it will truly be something you can be proud of. This is just a Demo, no shading, atmosphere or color correction was involved,  but I have done about two dozen shots since then, and there is no end to what motion tracking can be used for.

What are some examples of shots that may use motion tracking? Chances are you have seen the end result of Motion tracking in movies and TV and it has been so subtle that you may not have noticed it. But here is a list of some things that could use motion tracking for a shot:
 

* lightsabors, sparks, energy, lasers, knives and swords
* replacing whats outside of a window in a moving shot
* bullet holes on a getaway car as it speeds away
* missing limbs ( think Forest Gump's LT. Dan)
* Zombie head wounds, missing parts of face
* scars, robot parts underneath skin
* removing or adding tattoos on an actor
* retractable teeth or just tracking teeth or facial features
* censor bars or masks for interviewees
* blurring copyrighted/trademarked words in public signs or license plates
* removing or adding skyline elements to expand a city or set
* morphs or changes
* muzzle flashes from a gun
* fire on an actor
* replacing buildings in a skyline you do not have rights to use with fake ones
* set extension
* UFO's ( think "District 9")
* the list goes on and on (I have yet to come up with an end to its many uses)

Hope you enjoyed this nice little unrefined demo. It definitely opens up some possibilities to an exciting future.

TJPARSONS

Tom Parsons

The founder of Uddershiet Films and film enthusiast, maintains a fun collection of movies that he regularly references for technical examples, discussions with colleagues, friends, students, and production staff. Although there are particular films, shorts, and videos that he prefers over others, seldom is there a movie that he doesn't like.