Prevent snapping in camera tracking?

[SmithyOrSmithIfYouLike]

Hello.

I have a image that is attatched to a wall. I have done this using Track Camera. However, at some points, the image actually snaps to a new position to align itself.

Is there a way to make it smooth, over an interpolation if you will, instead of snapping?

[Mylenium]

Without seeing your footage nobody can advise. Such a behavior typically indicates that the camera is too close to the subject and therefore the orientation of elements flips back and forth. This may require extensive cleaning up of the camera motion more than anything else. A screenshot of the graph editor curve would easily reaveal such oddities.

Mylenium

[SmithyOrSmithIfYouLike]

For example, take the first few seconds of this video.

How to Attach Objects to Walls & Ground in Adobe After Effects CC! (3d Motion Track Videos Tutorial)...

You can see the top right video that is attatched to the wall is snapping a little bit when it repositions based on the camera movement. Is there a way to set that snap over an interpolation (just make it transition smooth to the new position?)

[Mylenium]

The camera in the example video simply has way too large a FOV and nothing was done to treat the footage to compensate for it. Or in other words: The tutorial is kind of rubbish and doesn't care to explain the prerequisites of a good track because the creator doesn't understand the requirements himself. And that's putting it politely. Any kind of tracking requires proper preparation and understanding how the underlying stuff works and it really is as simple as that. To eliminate drift and otehr oddities you have to know where you point the camera and use the proper technique like doing a manualyl calibrated track with lens compensation, which is not doen in AE simply because it's not supported. This requires tools like SynthEyes or other advanced tracking software.

Mylenium

[Rick Gerard]

You have got to vet your trainers. I give this tutorial a D because the workflow is inefficient, inaccurate, and there is no explanation of exactly what the camera tracker is doing. When he is moving around the first 3D object there is no effort at all make to maintain the plane of the original target. I could go on and on. The trainer kind of sorta gets things stuck to the wall but that's about it.

If your attached image "snaps" to new positions then either you have a bad camera track or the image is not attached to a surface in the composition. You also probably did not set an origin and ground plane. As Mylenium said, we'll have to examine the shot. If you are using the sample video then it is highly unlikely that you can get an accurate camera track if you do not fix some lens distortion first and be extremely careful identifying planes. The only keyframes that are generated when camera tracking are camera keyframes. and the only useful tracking points are ones that correspond to actual planes in the shot. Most combinations of tracker points are useless.

Show us your actual shot and a screenshot with the modified properties of the layers that are giving you problems revealed and we might be able to help. Without those details, it is really hard to tell what is causing the problems in your composite.

[SmithyOrSmithIfYouLike]

I don't really have any footage persay. But, to give an example, maybe this time it will be more clear.

If I have a solid (image) being tracked with the video (on let's say a road). And it is a flat image or some decal or something. Let's say I was going really fast and each frame of the road made the road move a meter up. The decal, ideally, would move with the road the same meter up.

Could I make it so that instead of it moving a meter up (and say the whole screen just shows 3 meters up to down), it moves instead 1/3 of a meter each frame or 1/4 of a meter each frame. It would still move in the same direction as where it should be, but half, a third or even a quater the distance.

This is my third project in AE so I don't really understand half of your terminology when you reply btw. Thank you though.

[Roland Kahlenberg · Accepted solution]

This tutorial author has close to 400,000 subscribers!!! He should not even be allowed to teach ONE other individual.

There's just so much wrong in this video! The way he moved/adjusted the tracked target on the left wall immediately screwed up the accuracy of the tracked point. He's also not mentioned how to look for good and bad tracked points.

To make the adjustments you want, I would look at parenting the layer to a Null. Then create position KFs to help you reach your goal. This process if of course done manually.

[Rick Gerard]

From your explanation, it is clear that you don't have any understanding of what kind of tracking you should be doing or how to do it. Type Camera Tracking in the Search Help field in AE and learn how that works. Camera tracking does not track objects in a scene, it figures out how the camera was moved and creates a virtual camera inside AE that moves just like the camera used to track the shot. This allows you to put 3D objects into the virtual 3D world AE has created for your object.

Motion tracking tracks the movement of areas of detail in a shot. It does not create a camera but instead gives you 2D coordinates for the detail you are tracking so you can stick other elements to those positions. You can track position, scale, and rotation.

Corner Pin tracking tracks the corners of rectangular detail in the shot, like a photograph or a sigh. This gives you the ability to replace those rectangles with other images. This is also 2D tracking.

Spend some time getting to know the UI and doing some studying. Just diving into AE and poking around is a horribly inefficient way to learn.

[SmithyOrSmithIfYouLike]

I understand the differnces of the tracking types. People seem to be missing the question of if it is possible to manipulate the camera tracking positioning system in the 3d world it has created for me. It is possible to scale down the interpolation of the movement of my object based on the tracking points in the 3d world?

[Roland Kahlenberg]

Are you not able to read my reply?

[Rick Gerard]

If you change the keyframes for the camera you destroy the camera tracking solution.  There is nothing keeping you from animating the position of any 3D layers you place in the scene, It is just very difficult to keep them looking like they are attached to the scene. If you do not set an origin and ground plane to start it is almost impossible to figure out the 3D geometry.

From your description, I think that you may be better off with Motion Tracking than Camera tracking. I'm still pretty much guessing about the shot you are trying to create.