Skip to main content
Hossein.foto
Participating Frequently
January 20, 2017
Question

3D camera tracker problem

  • January 20, 2017
  • 4 replies
  • 2399 views

Hello guys!

I used 3D camera tracker but I don't know why in a part of the video the points suddenly moves. Please check the link below, I provided a screen record.

screen - YouTube

P.S: I used "Tripod pan" in "Solve Method" setting.

Regards

This topic has been closed for replies.

4 replies

Kevin-Monahan
Community Manager
Community Manager
February 6, 2017

Hi Hussein,

Sorry for your struggles with camera tracking. Some great advice here. Did any of these posts help solve your issue? Please let us know, as these kind gentlemen did volunteer to help you. If you do need additional help, please let us know that, as well.

Thanks!
Kevin

Kevin Monahan - Sr. Community & Engagement Strategist – Pro Video and Audio
Community Expert
January 20, 2017

As I said before, if you want to insert some objects outside the windows of those objects approach the edge of the frame you're going to have to remove the lens distortion because things will not line up.

I would trim your footage to just the frames where you want to add the objects, then trim the composition height and width so you do not have any black bars,  then apply lens correction to try and remove the distortion at the edges, then pre-compose moving all attributes, then camera track the pre-comp and insert your 3-D layers.

The only other option is to stabilize the footage so things don't move and do the composite entirely in 2D, and then put the motion back in everything. Neither one of these is going to be easy or automatic.

Szalam
Community Expert
Community Expert
January 20, 2017

And, again, do all of that AFTER you convert it to a proper production codec first to get rid of the weird H.264-ness.

Roei Tzoref
Legend
January 20, 2017

in addition to what Szalam mentioned, here are my pointers:

I see you already made some compositing and what not. start fresh and:

  1. make sure your composition and source footage frame rates match
  2. select the start and end points of your footage layer in time you wish to track and trim it accordingly
  3. apply the 3D Camera tracker. this looks like a Tripod pan but let Ae try for itself. you can always change it.
  4. check your average error and see if it's below 1 pixel.

if this does not work, come back with the results. if you can, upload the footage so we can try for ourselves and maybe guide you through the process.

Hossein.foto
Participating Frequently
January 20, 2017

Thanks Roei for your reply.

1. composition and footage frame rate is same, 25.

2. I did this but I faced to this problem.

3. AE couldn't solve camera in other options and just in Tripod pan it worked and that's why I chose this one.

4. Average error is 6.09

Here you can download the project file, NOT footage because I have some mask layers and maybe it helps better.

final-02.aep.zip - Google Drive

Here is the footage also if it helps:

footage (1).mp4 - Google Drive

Thank you

Community Expert
January 20, 2017

How much of that shot exactly are you trying to track?

You should trim the shot to the exact frames that are going to be used in the final composite.

If your 3-D object is going to approach the edge of the frame then you must remove the lens distortion before you do the 3-D tracking. If you do not already have a lens profile then you will need to make one up or do some experimentation. There is an awful lot of lens distortion in your shot, maybe as much as 20%.

The footage has also been cropped. You should be using the original full frame footage for tracking because you will end up with a much better solution.

If you get into this kind of situation again and have any control over the shooting make sure they shoot a grid with the camera and lens they are going to use in the production so you can accurately calculate and correct lens distortion to do your compositing. Wide angle lensa distort at the edges but the AE camera or the stock camera in any 3-D app has a perfect lens so you have to remove the distortion before the shit will accurately track all the way to the edge of the frame.

Szalam
Community Expert
Community Expert
January 20, 2017

What, exact, version number of AE are you using (down to the last decimal point)?

What format and codec is that source footage?

Hossein.foto
Participating Frequently
January 20, 2017

I use After effects CS6, version 11.0.4.2

Video details:

.MOV

Video codec: h264

Video BitRate: 9959

Video FrameRate: 25

Szalam
Community Expert
Community Expert
January 20, 2017

Use Adobe Media Encoder to transcode that footage into a proper production codec. H.264 in the MOV wrapper is pretty buggy and has never been supported by Apple.

By production codec, I mean something like QuickTime with the Photo-JPEG codec or QuickTime with the PNG codec.

Then try tracking that new video file instead.