Camera Shakify works in viewport but break initial-camera movement in Rendering animation

[OutsideTheDome]

Blender Version
Blender 4.4.3 - Windows

Describe the bug
Camera Shakify doesn't "work" when rendering a video.

To Reproduce

1. Add a Camera
2. Record animation (handmade type of movement)
3. Add Camera Shakify
4. The "shakify" addition works in the viewport
5. When rendering the video, the Camera ONLY use the Shakify movement, in place, and bypass all the other movement I've recorded.

[Cerbskies]

I've had this similar issue. It wasn't always the case but it started happening a few months ago. The only way I've fixed it was to Bake the camera movement and delete shakify when you're ready to render.

Unfortunately simply turning off the modifiers will still corrupt the movement at render / batch render time. Needs to be deleted.

[cessen]

Sorry for the delay on this (I've been quite busy with other things, and I maintain this project purely in my free time).

I've been unable to reproduce this on 4.5.3, although it seems to still be happening in 4.5 (#50). A simple, minimal blend file that has this issue would be really helpful in tracking it down and fixing it.

[Cerbskies]

Sorry for the delay on this (I've been quite busy with other things, and I maintain this project purely in my free time).

I've been unable to reproduce this on 4.5.3, although it seems to still be happening in 4.5 (#50). A simple, minimal blend file that has this issue would be really helpful in tracking it down and fixing it.

I uploaded a completely new install version of blender 4.2 LTS. No addons, completely fresh install with just shakify installed. Same problem. Render the animation IN blender and it will render the motion correctly.

Rendering with batch render / command prompt out of blender and it will show shakifys movement but will lock the camera in place.

untitled.zip

[Cerbskies]

Any possible fix? It would be an immense time saver if this was fixed.

[cessen]

Sorry for the delay again. I'm still quite busy, and likely will be for a while. I've now looked into it briefly, but wasn't able to reproduce on either Blender 4.3 or 4.5.

What are the command-line arguments you used for rendering from the command prompt? This is what I tried:

blender untitled.blend -b --render-anim

Also, are you rendering on the same computer when you do the command line/batch rendering tests (e.g. you're not farming out to other computers)?

[Cerbskies]

Yea same computer. Not using a render farm or anything.

If I'm rendering with command line I use:

"C:\Program Files\Blender Foundation\Blender 4.5\blender.exe" -b "PATH TO FILE" -a

But I use an addon called Blender Render Que mainly. It does not matter if its command line or addon. The problem will persist in simple files like the one I uploaded.

Could it possibly be GPU related? Nothing in my hardware has changed other than my NVidia graphics card. I run an RTX 3060. Besides that I cannot think of what I did to cause it. I just remember noticing one day that my Camera did not render any movement I had besides the shaking from shakify and its been an issue since. No matter the blender version I use.

[cessen]

I can't repro with blender -b untitled.blend -a either (renders the animation with the sweeping camera motion fine).

Another possibility is that it could be Windows-specific (I run Linux). Unfortunately, I don't have a Windows system to test on.

In any case, all of this is making me think that this is probably(?) a Blender bug rather than a Camera Shakify bug. Camera Shakify actually does very little: sets up some constraints, some drivers, and adds a handful of custom properties. And that's it. There's no fancy/crazy stuff going on, and almost entirely stuff you could set up by hand as well.

So the fact that this file is behaving differently across different systems, and also between UI-launched and command-line-launched rendering feels like a Blender issue (can never be 100% sure, of course).

It might be worth filing this on the Blender issue tracker, with as much detail as you can provide (system specs, OS, example file, exact command-line arguments, Blender versions you've tested, etc.).

I'll leave this issue open just in case, though.

[Cerbskies]

Too add to the issue, besides camera transforms being locked in place at render time, other parameters like Focal Length is ignored when using Shakify at batch render time.

Just the shaking from shakify is registered.

[cessen]

other parameters like Focal Length is ignored when using Shakify at batch render time

Oh, that really sounds like a Blender bug, then. Thanks for the info!