(Solved) Camera Placement Discrepency between Viewport and Render

I am working on an animation, and there is a large discrepancy with the camera placement between the ViewPort and Render. It happens in blender internal and cycles.
I created a new document, linked the Vehicles and the scene in, and animated it. Then I parented the camera to one of the vehicles. In the viewport everything looks ok, while the camera lags a few feet back. I am using blender 2.63 for mac r46461. Although there is a one frame discrepancy, the results are consistent for both render and external.

Is this an issue with the Dep Graph or whatever they call it? If so, how do you recommend I work around this issue. The camera is parented to a bone in the Car’s armature.

I can provide a blend file through PM, so let me know if you would like to check it out.

http://www.pasteall.org/pic/33560
http://www.pasteall.org/pic/show.php?id=33560

http://www.pasteall.org/pic/33561
http://www.pasteall.org/pic/show.php?id=33561

Perhaps you accidentally have a keyframe for the camera?

the only thing is that the viewport is exactly what I want.

I’m just going to post the blend files.

Which blend file is for the images you posted above?


Odd… It seems to have rendered just fine for me. This is from the ‘CarAccidentMaster.blend’

After looking at my file again, it seems that it works ok when you render it as a still image, but when you render it as an animation, the camera goes to the wrong place. Can you try rendering a frame as an animation.

Ah yes, same problem when I render as an animation. The first frame (362) seems to appear in front of the car, and then the following ones go to that position further behind the car as you posted above. I’m just packing things up since I am out of town, but I will look more closely at your blend file when I am home to see if I can perhaps see why this is happening. Very strange at first glance.

if it’s when you render an animation, and if it’s only for the frame 362, you can render your animation as image sequence, and then replace the image 362 by rendering it as an still image and then you can create your video from this image sequence.

Mathias.

Hello niverik2k,

After looking at your file and I found it might be a problem due to ‘direct parenting’ of the camera (Angela OS.v2) to BMW3_Armature rig. This may work in some cases but not highly recommended as it makes your camera pop-in front and back at certain instances.

To overcome this issue, remove the direct parenting [hotkey: Alt + P] and use ChildOf Constraint instead.
Target: BMW3Grp_proxy
Bone: Move

Finally, offset your camera as you would like to get the POV of the driver in that car.

Let me know, if that worked or not.

PS: You’ve got an intermediate level of scene file there, just make it little more organized (i.e. put the linked .blend files in proper hierarchy, like make directories for props, environment-sets and a separate one for the scene files). It will not only be less cumbersome for you to manage your data assets at any point in time but would also help others (if they’re working along with you as a team). Good luck! :slight_smile:

Thankyou Exzema mathiasA, and BigMoose I was able to resolve the problem.

@ Exzema, that was the problem, when I used the Childof Constraint. My question for you about the PS, is that I heard it was bad to move linked files. is it possible for me to move linked files into a folder and have everything still work? How can I make sure not to mess everything up? Is it always better to use a child of constraint, or does it only apply to cameras?

@ mathiasA, it was having the same problem regardless of whether you rendered it as an image sequence or a movie.

@ thankyou again for taking the time to look into this.