Influence on Object Constraint and Visual Transform ruins earlier keyframes

Support Animation and Rigging
1

So I have a camera parented to a null object following a path with the follow path constraint, which works fine.

I want the camera to focus on an object at a given time and then after some time stop focusing on that object. For that purpose i use the Object Constraint Track To, and manipulate it with the influence. This works fine, but the problem occurs when I want to stop focusing on the object and just control the camera with regular keyframes. I remove the influence, and the camera moves to another position than I want, but I fix that using CTRL A → visual transform.

But now, when I got to my earlier keyframe (with the Influence being 0) the transformation of my camera is all wrong.

How can I keep my early keyframes and also do the Visual Transform after I’m done tracking the object?

Thank you

Influence1.PNG
Influence1.PNG1869Ă—884 209 KB

2

What do you mean with “control the camera”? Move it? Control the focus?

Why instead of using track on the object you don’t track the focus on an empty that you move to the object you want the moment you want?

3

Sorry for being unclear, I want to control the transformations of the camera.

That was a very good idea sir! Then I can use that empty to always control the direction of the camera, while being free to transform the camera as I want.

I will try that :slight_smile:

1 Like
4

You need two sets of keyframes. First keyframe position and influence (at 1.0); then advance a frame, apply visual transform, set influence to 0, keyframe location and influence.

5

Not only that, you can also set the empty as you depth of field target in the camera settings and it can control the DOF around the scene. If you are using DOF in the render and not in compositor, of course.

6

That was what I was trying to do, but the second keyframe’s transform (the visual transform) would translate back to the first keyframe.

Im sure there are many ways to do it, but for know I’m just using the method @Calandro suggested :slight_smile:

7

Not sure I’m getting you-- to the same numbers, or to the same world-space transform? It’s supposed to be the same world space transform. That’s why you do the visual transform, to get the same world-space transform.

Frame 10: Set constraint influence to 1.0. Keyframe influence and loc/rot/scale.
Frame 11: Apply visual transform. Set constraint influence to 0.0. Keyframe influence and loc/rot/scale.
Frame 20: Rotate, keyframe loc/rot/scale.

8

Ok. So when I did that, my frame 10 would be off. The camera would be rotated away from the original camera position equal to the rotation done by the visual transform. I’m not saying you are wrong, maybe I’m just too much of a blender noob to get it to work :stuck_out_tongue:

9

You’re saying that applying the visual transform on frame 11 affects the keyframed loc/rot/scale of frame 10? That shouldn’t ever happen. I’d want to see a file to reproduce it.

(I forgot to mention to keyframe constraint influence at frame 10. I’ll edit the message to that effect. Hopefully, that’s what you were doing anyways.)

10

Ok good sir.

I recreated my problem in a new much cleaner blender file.
Using your method it works! :smiley:

On a sidenote I found out, that the x next to Influence is used for this purpose :slight_smile: Influencex

Thank you!

11

And now that I’ve earned a trust level on this forum, I can upload the file so you can see for yourself :slight_smile:
This method also works on the ChildOf constraint :slight_smile:
InfluenceAndVisualTransform.blend (901.7 KB)