Path Animation not Accepting Keyframes

Hello to you all…

I have set up a camera on a path (Curve>Path) and I want to regulate the speed. According to various tutorials, I should be able to set keyframes on the Evaluation Time field for the path and use that to regulate the speed. I know this works because I did it once before, but now it doesn’t work… I try to set a keyframe and I get an error message:

Can anybody direct me to step-by-step instructions on how to set up a camera on a path so that I can regulate it’s speed? I know there are different ways to set this up and I just happened to do it a way that won’t allow keyframes. So what is the right way?

(Tthe Blender docs just confuse by talking about there being different ways to do it without really explaining any of them. May as well not be in there at all!)

Okay, don’t all answer at the same time! I figured it out on my own, even if it wasn’t the way I did it before.

I had to delete the f-curve in the graph editor before I could add keyframes.

There is a better way, but i don’t know what it is.

Nope, it’s not working again!

After I deleted the f-curve for the curve in the graph editor and added keyframes, it worked and I was able to see and manipulate the keyframes in the graph editor. When I tried to do the same thing again with another curve/camera setup in another file., it didn’t show the keyframes in the graph editor and the f-curve is a straight vertical line set at an obscure point on the x axis.

What’s going on? How do I properly set up a camera on a path and control its speed?


the best way is to add a follow path constraint to the camera, and check “fixed position” - then you animate the value below. Both objects have to be zeroed-out otherwise the camera movement won’t match the path.

The other method you mentioned is to parent the camera to the path and then use the evaluation time value to animate it, but that’s a bit inconvenient because
1/ you have to parent the camera to the curve and you might not want to do this if the camera is part of a rig
2/ every object parented to the curve and animated along it will do so exactly at the same time