Ok so i’m going to try and explain a simple track so i can show i know how to do it. First things first load the image sequence, set the frame rate it was recorded at and the last frame you want to track to.

Once loaded you can run an auto track and see what it picks up. This gave me 548 tracks, but not all last for very long. So if you go to clean assist you can decide to keep so many tracks per shot and only keep ones that last for so many frames.

You dont need to run an auto track, you could just track manually or do both. But you need at least seven tracks.

To manyally track, right click and select new track. Make the bounding box large enough to cover the tracking point and give it some area to work with. You can then, depend where you are in the time line, tack forward or backwards.

The area at the bottom of the screen allows you to see the quality of the tracks. Green is a Confident solve, yellow is not so confident and red is not confident at all. You can go back over these red points and re position the tracking box in place and repeat until you have just green or yellow tracks. Once you have all the tracks you need you do a camera solve.

Once you have solved the camera it will tell you the quality of it at the top of the list of tracks. Again green is good, yellow not so good, red bad. Really you don’t want any red on your camera solve, it means that the computer isn’t confident about its camera calculations. So revisit the red frames it isn’t sure about and try re positioning the tracking box and try get the tracks green. I found that after doing this and re- solving the solve would be more confident and turn yellow or green.

Once you have a good solve you need to create a new co-ordinate system.

Here you enter the distance between tracks and dictate an origin point. It’s at this point i would get confused, with what number goes where and in X, Y or Z. But Matt showed me an easier way to achieve the same result. By switching it to 3d mode you can drag the X and Z point to where you want it, this is so much easier to get my ead around. This is so it can determined which way is up and how the surface sits.

You also need to input some details about the camera. you need the focal length and size of the film gate.

Once this is all in place, if you go into 3D mode and press C you can look through the camera and see how the grid sits in the image. There is also an option to place a ghost cube in the scene. Below is a screen shot example from anther track. By scrubbing the time line or playing the footage you can see if there are any problems or sliding occurring.

Once your happy with the track you can export it as a MA maya file and open it in maya as a renderable camera.

Below is a play blast of my independent track, i can now confidently say i can produce a simple track.

Time for a large one now….

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