Saturday, January 26, 2013

Object Tracking in MatchMover and After Effects

Hello everyone!  This blog starts my journal on my progress for my Motion Imagery class.  We are going to go over MatchMover, After Effects, and Nuke.  The tutorial that I am currently on is called, "Object Tracking in MatchMover and After Effects" hence the title of the post.  First I want to give credit to Digital Tutors for helping me learn multiple programs and giving me free content to work with (models, textures, etc.).

Alright, here is what the tutorials went over.

First lesson was just a review of the course.  The second lesson went over the correct environment you should have when starting in MatchMover.  The camera footage that you are using should include the objects you want to track.  However, it was mentioned that it is important for your object(s) to stay fixed to something (not move around or deform a lot) and should have various depths or levels in the environment.  Reflections can also be bad for MatchMover.  Here is screenshot of what the instructor thought to be an acceptable object with "tracker points".

 
Making "tracker points" (the pink pieces of paper) will make it easier to track in Matchmover and replace with other "3D trackers" and eventually objects or 3D models.

In the next lesson we started placing trackers into our picture frame scene (footage).  The instructor knows what he is doing, but sometimes he presses keys without telling you what he is pressing.  I figured out that he was pressing F3 to track forward and F4 to track backward.  I was also confused on what the coloration of the trackers meant and so I looked it up.  Here is autodesk.com's explanation, "The colors indicate the quality of the tracking, where green indicates good, yellow fair, and red bad tracking.  Some grayed tracks have not been reconstructed, which means that MatchMover considered them unfit to calculate."

If there is an area that is yellow or red you can go to that keyframe click on the point where you want to track again and either track forwards or backwards depending on what direction you need to clean up.  The more green that you see in the tracks' timeline the better.  Here is a video showing where I placed them.


The next lesson went over setting up the focal length, solving for the camera, setting up a new coordinate system, and exporting the scene to Maya.  Here is a video showing this.


In the following tutorial the instructor opened up a rendered object (in this case a female head) and imported the MatchMover camera that we set up in the earlier lessons.  Here is a video showing it moving with the rendered object; pretty cool.


The next lesson was interesting.  I learned how an HDR dome can affect the lighting cast upon your objects' surface.  I also learn a little bit about how to bake in renders using the Final Gather map.  This can save you render time in the future.  Whenever your lighting changes you have to turn the Final Gather map back to the "On" position and re-render your scene so that it will display the correct lighting in the other renders.  Here is a semi-longish video showing some of this.


The next video showed how to make the reflective glass surface for the picture frame.  Using the "create polygon tool" we created a square by snapping the points to the four points of the trackers.  We then created a reflective surface and tweaked some of the settings.  Look at the video for an example.


In the next tutorial the instructor showed me how to create a cutout matte by duplicating my reflective image plane, hiding the duplication in the reflection layer, and then revealing the duplication in the masterlayer.  We then added a surface shader and extrude some of the plane faces outward until we only had parts of the face that we wanted.  Here is a video showing an example of this.


The next lesson was a bit over my head, but here is what I got out of it.  He duplicated the reflection layer and then added the head and the black cutout matte.  He then went through all fancy the render menus changing some attributes.  He then rendered out the head out and everything looked correct.  I was able to duplicate what he did, but I did not quite understand his explanation of what Alpha layers truly were.  Look at this video to see the changes from the last video example.  (There is still a glare on the girl's nose that I am not able to get rid of; I wonder where I went wrong).


Haha!  Finally we move on to Adobe's After Effects.  The tutorial just talked about importing footage and how to drag it into the timeline.  I was a bit frustrated though because he didn't exactly explain where to drag the footage that was imported in and he talked and did everything really fast.  Here is a video showing how to import footage and sequences into Adobe After Effects.  To get the footage onto the timeline you can click and drag the footage to the small film strip icon located below the project files.


In the next tutorial we did some basic compositing and set up our occlusion layer and color layer properly.  The instructor also advised setting up the items of the project in an orderly way.  Here is a video showing the what the settings look like so far.  I don't quite understand all the tools he is using at this point because I have never previously used After Effects.  Video!


In the following lesson we went over how to work our reflection layers into the compositing process.  It went over  the use and result of using reflection for the foreground and background.  Press "command  D" to duplicate the reflection layer and then place it in the correct order in your layer heirarchy.  You can press the "T" key to set the Opacity of the layer.  Here is a video showing how everything is set up.


The next video showed how to use key lights and masking.  After the video was over we were able to properly mask out the thumb.  Here is a video showing the necessary components to mask out the thumb and the trackers and still maintain the reflection.


The next tutorial showed how to use an alpha blur and an alpha mask to soften the bottom edges of the the neck/shoulders.  The explanation and steps were a bit quick though so I don't think I will remember how to do it again perfectly.  Here is a video showing the final result after following along in the tutorial.


In the following lesson we went over how to use a reflective matte (one that we already created) to help keep the detail in the hair, while still softening up the edges of the lower neck and shoulders.  We made an animated mask to soften up the lower neck and shoulders and maintained the detail in the hair.  This video should what I mean.


In the next tutorial we went over the benefits of using the Color Correction tool.  We used the Hue/Saturation and Exposure tools to find a happy medium where all elements of the scene would match up in color.  Here is a video showing the differences before and after the color correction.


Yes!  I am on the final lesson.  For the last lesson we went over correcting some of the image's perfection by adding the "fast blur" effect.  The reason for this was to try and match the background to the foreground and things in life are not always in as pristine condition as a computer can me it look.  Here is a video showing the final look of the compositing.


Well guys thank you for looking through my blog (whoever looked) and hopefully some of this may have been helpful to you and given you an idea of what you can do when you combine programs like MatchMover, Maya, and After Effects.  Until next time!

Oooo here is my final render.  I also put it on loop a couple times so that you can see it (again and again and again and again and again.....).  Well you don't have to if you don't want to, but here it is.



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