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[Asimov500]

Hi all,

I am new to this forum.

I have a shot where the camera pans to the right and then to the left. It is shot in my living room. I want to put the 3D object onto a table. I didn't have any dots or anything in the video to track, and so I had to use any markings I could to do the track.

Anyway I put trackers on 3 corners of the table, as the 4th corner is out of shot most of the time. Also I put some trackers in the background of course.
The trackers all seem to track fine, on the 800 frames of the footage.

However when I do a solve things go a bit wrong. It starts off fine. The little x's are following my trackers, until the camera begins to pan. Then the table x's leave the trackers and follow the camera, instead of staying put.

In other words if I put a 3D object onto the table, it starts off looking fine, and then looks like it follows the camera rather than staying on the table.

I would have posted pictures, but not sure how to on this forum.

Any help would be appreciated.

Asimov

[GraphicsKid]

It sounds like it's not really solving the whole shot. Go to the perspective view. Does the little cg camera there mimic the move, or does it stay still?

[Asimov500]

Hi GraphicsKid,

I think you were right. The camera didn't seem to be moving in the top view.

Anyway I have kind of solved that problem. I used tripod solve. Only this has caused other problems. Now my camera is turning in an arc.
I have a few jumping trackers I am trying to control.

I think the problem is that I have picked tripod and there is a movement on the camera in one shot. So the item on the table starts to slide LOL.

Also all the x's in the top view are in an arc, so I can't place my object properly. I place it flat and in the camera view it is on an angle. I set the origin the left and the plane thingy, but that didn't really cure it.

I know it sounds stupid, but I have been trying to do this for 3 days.

On an older project I managed to do a successful track, but this one is alluding me. I think I will have to find some more tutorials and do a lot more studying.

Asimov

[GraphicsKid]

If there's even a little bit of perspective, you should be able to pull off a 3d track, even if it is on a tripod, because it's likely the tripod's center of rotation isn't in line with the camera's focal point (which is where you want it to be for a "perfect" tripod shot: ZERO parallax).

How many trackers do you have going at any one time? 3d tracks require more trackers than tripod solves.

[Asimov500]

Hi GraphicsKid,

I did have about 20 trackers, but I have tried something. I locked off some of the important trackers, and then I did an auto track on top. It kept my trackers in and now as the camera pans it is much smoother. It probably has about 50 odd now, although I haven't counted them.

It is ok up to the point where the camera starts to move, and the plane on my table then starts to look like it is angling.

I do not think I am going to get it better than this, so I think I will try this.

I am going to export to max. Put my plane and my object onto the dummy I created it in syntheyes, and on the last couple of frames I am going to key frame it tilting to match the camera view.

It only happens in the last 50 frames or so. I hope this idea works. My ground plane will have an matte map so that I will see the shadows on the surface of the table.

I might record my syntheyes with camtasia to show you, when I have more time. Perhaps it will shed some light on it.

PS here is a link to an old project where I had a successful track
http://www.youtube.com/watch?v=9ZlVqvkp-d0&feature=mfu_in_order&list=UL

Asimov