3d camera tracker and time remapping used together

[maxxt70668201]

Hi, I am somewhat new to adobe after effects and have been having a problem using both 3d camera tracker and time remapping in the same clip. I remapped my clip the way I wanted and then turned remapping off to use the 3d camera tracker but my clip always goes back to the regular speed. Do I need to use this "pre-compose"? Can someone give me a step-by-step? I am using it for cinematic shots from a slow moving free camera in a video game.

[Roland Kahlenberg]

I would Time-remap first and then precomp for the Camera Track.

[Rick Gerard]

First, camera tracking may not work with game capture footage because the perspective and parallax changes may not be accurate.

Second, there are two methods of working with footage when you want to change the playback rate.

If you want to slow down (make slow-motion) a clip using any method including time remapping and you want to do any kind of tracking or compositing with that slow-motion shot it is critical that you either pre-compose moving all attributes and then track the nested comp or render a suitable DI (digital intermediate) using a production format and then use the rendered shot for your tracking.

If you are speeding up footage you will get much better results if you camera track or motion track the footage first, do the compositing and add the effects, and when the shot is finished, pre-compose and speed up the pre-comp.

Last point. If you are doing any kind of timelapse it is important that you interpret the footage at the proper frame rate and make the frame rate of the comp match the frame rate of the footage. Then you do your tracking, compositing, and all the rest. The last step is to pre-compose or render and then time remap. Motion Tracking and Camera Tracking are extremely difficult to do with timelapse footage so be prepared.

[maxxt70668201]

Thanks so much for the reply!

The tracker does work with this specific clip, I just can't get it to work with time remapping. I am using the graph and having the clip speed up at the beginning and end of the clip and slow down in the middle. The clip is 60fps. How would you recommend going about this?

[Rick Gerard · Accepted solution]

The easiest option is to camera track do your compositing and then nest the comp you have edited in a new comp and time remap that comp. That would be the same thing as selecting all of the layers in your comp and pre-composing them, then time remapping the pre-comp.

The only other option, which probably would not give as much accuracy would be to time remap the footage layer, pre-compose and then camera track.

I hope you understand why you cannot camera track footage and then time remap the footage and have the camera still follow the action. You will get it if you select all of the layers in your comp and press the U key to see what has been modified after you camera track footage and add a camera and a 3D layer. Only the camera has keyframes. Keyframes are based on time. Time remapping changes time so the camera is now out of sync.