Keyframe stretcher makes black frames instead

Does the keyframe stretcher work with 3D nodes, animated? Instead of stretching my animation, it's just rendering blank black frames once the clip reaches the source end frame. This is on a fusion composition. I tried copying all of the nodes into a fresh composition but the problem just persists. I'm confident that the keyframe stretcher itself is setup right.

You appear to be using the wrong node for what you are trying to achieve. The TimeStretcher or TimeSpeed are most likely what you need. These would need to be placed after the Renderer3D. I think there is also a 3D version that could presumably be used in amongst the 3D nodes. Someone more familiar with 3D will be able to advise you.

You appear to be using the wrong node for what you are trying to achieve. The TimeStretcher or TimeSpeed are most likely what you need. These would need to be placed after the Renderer3D. I think there is also a 3D version that could presumably be used in amongst the 3D nodes. Someone more familiar with 3D will be able to advise you.

But I'm not trying to do slo-mo type effects, I'm trying to make a given fusion comp stretchy so that the animation fills the length of the clip.

Can you share the setup with us? I don't know if keyframe stretcher supports 3D, but it took me a long time, before I understood that keyframe stretcher always works relative to the full length of the clip.
So outputting black is weird. Depending on your setup it should at least output the final frame of your animation.

I think I just found the solution on accident. From the Edit page, I needed to change the clip duration to match the keyframe stretcher "Source End" value. After doing that, I was then able to stretch the clip to whatever length I wished for.

I wish I knew how this duration had been set differently in the first place. I'm guessing it was inferred from the initial clip length in the timeline. Also, there seems to be some weird interaction with another clip, an adjustment clip I had placed above it, which was applying a blur effect for one portion.