Camera Tracking Problem

Artistic Support Compositing and Post Processing
1

I have attached a blend file I am having trouble with. I am attempting (for the first time) to use the camera tracking feature in blender, and made this short video for an exercise. The problem (as you can see) is that when I set the floor, regardless of how I set the x and y axes results in the camera flipping to the top. I have attached one image since the zip containing all 151 images in the sequence will not upload for some reason (it is only 5.5 MB so I have no idea why it won’t accept it).

The camera I used is a Fuji Finepix JV100. I know it’s a cheap camera, but I figured it was as good as any to use to learn with, and it’s the only “video” camera I have available to me. The specs on it are at:

http://www.fujifilm.com/support/digital_cameras/specifications/j/finepix_jv100/

Whether I set the focal length to 19.8 mm or 37 mm seems to make no difference, and I have no idea what to set the sensor width to (says the CCD is 2.3" wide, so I set it to 58.42 mm, which changes the focal length from 19.8 mm to 36.147mm).

My average solve error is only 1.5407 which I figure based on research is good enough for a quick “how to” effort. When scrubbing through the footage the tracking markers look really tight.

Any ideas, advice or help would be appreciated. I tried removing markers in case I had too many but get the same result.

Attachments

zenaBall3.blend (545 KB)

Z_ball_00001.jpg1280×720 38.6 KB

2

I found a solution of sorts for this particular scene. I just rotated the camera around the cursor on the X and Y axes until the 3D “floor” lined up with the background footage in the camera. This worked so-so for this simple scene, but for more complex ones (like the one I’m working on now in which the camera “follows” an object down a street, pauses in front of and under the camera, then continues on out of scene) this “solution” won’t work.

I’m going to play with various camera data settings today once I get the new footage tracked and see if I can zero in on what works for my cheepie camera. If I figure it out I’ll post the results in a new post for a Fuji Finepix JV100, but anyone who has some clue why this is happening at any stage in the process I would be glad to hear from.

<edit> link to solution video provided: https://vimeo.com/54137158