Camera tracking giving me headache

Hello guys! It’s been a week that i’m really trying to solve this problem, but it seems that it is stronger than me. I’ve researched everywhere, in english and in my native language (portuguese… sorry if i made some mistakes) and i can’t find a solution. Anyway, i think i’ve made everything right. Put the right camera settings, lens, lots of markers. solve error is between 0.7 and 1.6, so i think it’s ok, right?

Well, when i setup tracking scene and go to the 3D view, the markers spread all over the “space”. So, when i set three markers as my floor (in Movie Clip Editor), it never gets right. Actually, it also happens that, if i put a cube (for example) it “walks” a little from one side to another, not keeping its position.

Hope you guys can help me, couldn’t find answers anywhere :confused:

it sounds like the problem is some of your markers aren’t tracking properly. the markers that you intend to use in your solution, you should place manually, and scrub through the frames, making sure they all stay on track. if one gets askew, you may have to adjust it manually for a few frames. if you want your scene to appear like a point cloud of markers, though, and don’t care about the exactness of each marker, use weighted tracks for those markers.
(edit) and try to place your markers at places that are visually unique, and stand out well. if you have some polka dots and they all look the same, blender will have difficulty distinguishing between them.

Hi, Modron! Actually, i’ve placed all the markers manually (at least 15) and i’ve already checked if the markers are running away from their place :confused: I think the problem is in the fact that when i go to 3D view, they’re not acting as if the were in the same surface. For example, I marked some points on the floor, others on the wall, etc. The markers that should be representing the floor, if I create a plane, I can’t put all of them in this plane because all of them has different positions. However, if I look through the camera, they’re alright.

I am not sure what the problem is, but I am thinking if you added a bunch of zero weighted tracks, it might shed some light on the problem.

i had the same problem, used a cube, and kept sliding. Once i rendered it out it was rock solid. You can see the video at youtube page below. There is foot slippage but thats from the walk cycle. If the problem is the same, then it s the way the 3d view updates and displays video. From what ive been told on this forum its better to use image sequence than a video.

Try the automatic refinement (in solve panel). Set it to Focal Length and K1+K2. That will estimate the correct focal length and the lens-distortion.
Also, maybe you have to adjust the keyframes A+B. If in the first 30 frames the camera didn’t move and didn’t generate enough parallax, try to set Keyframe b to something later where the camera is moving a bit more. Maybe try 100 or so.
Getting the keyframes right can be a crucial part for a correct solution.
And then of course select the floor plane.