Bug: Camera Crane breaks camera

Hi all,

I’m trying to animate a camerarig_crane actor.

I create the actor and a new cine camera, attach the camera to the actor and zero out the transforms on the camera.
I add Crane Arm Length, Crane Pitch and Crane Yaw to be tracked in the sequence and animate those.

The first keyframe will be fine, but as soon as I add a second key, the camera is looking in a weird direction.
Checking the transforms on the camera reveals nothing and all it’s rotations are still zero.

Is this a known bug and is there a work around for it?

Best

Looking through the components, I found that it added
-63.087299 ° 0.0 ° -90.000595 ° of rotation to the CraneCameraMount(inherited) component.

Where is that data coming from and why is it being added?

Once the crane is broken, there is nothing I can do to bring it back.
However, converting the project to 4.13 preview fixes the problem.
Even after it broke, it plays back correctly in 4.13 (preview 1).

And it broke again :frowning:
I’l keep reporting my observations here.

Hi StoriesAG,

Can you provide some steps that may help identify the issue? Are you keying the camera at all in sequencer or just the crane? Can you also send along a screenshot of your sequence?

Hi

Thank you for taking the time to look into this.
I listed all steps I took in the top thread.
Nothing much more to add :frowning:

There has been a new development though;
I deleted the Intermediate and Saved folders and that fixed the issue.
It breaks again now and then randomly but deleting the folders again fixes it.

One problem that persists though is that when I tweak curves on the camera or the crane, the view snaps to some random location and then snaps back once the curve has been edited.
To make sure, I explain this right:
I click and hold on the curve handle and the view snaps to some random position and orientation in the world, I move the handle and let go of the mouse button and the view snaps back to where it’s supposed to be after the curve edit.
I think those two issues may be related but I’m not entirely sure.

Best

Hey ,

Thanks for the update. I’m following your original steps, but cannot get this corruption that you seem to be getting. Can you reproduce this in a blank project and then zip it up (with the Saved and Intermediate folder) and send it to me? With those two folders it may be to big to attach, but you can use Google Drive, Dropbox, etc.

One additional note is that the camera mount is there to counter the Pitch and Yaw of the crane. I’ve entered a bug (UE-34924) where the Yaw is not properly counteracted. However, you probably don’t want to be making transform keys on the Camera Mount Component.

Hi

Please follow this link to the project:
https://www.dropbox.com/s/d7k5n9op8irlt9z/Crane%20and%20Attach%20Problem.zip?dl=0

I recreated a similar path to the original and it did in fact break again.
We’ve used sequencer a lot and this is the first time it broke so badly.
My suspicion is because I’m going from a negative to a positive value in the camera pitch. This is the only sequence where we’ve done this and it’s breaking consistently.

What you’ll likely see is the camera looking at clouds.
What you should be seeing is the camera looking at the ground close to the origin of the crane and then move up and look down at the circling butterflies.
PiE actually plays back the correct path.

This will allow you to observe my other issue which you’re also tending to here:

Hidden inside the player start (I forgot to move it, sorry) you will find a butterfly that is not following it’s motion path.

Since I deleted the intermediate and saved folders the problem has been solved for me in the main project. I’m terrified it’ll break again but for now it’s fine so right now this is more QA for sequencer and not of super high priority for us.

Best

Hey ,

I was able to boil this down and reproduce it. It is entered as UE-34968. Thanks for reporting it.