• Adobe After Effects

  Dolly track removal advice

  Posted by Stuart Samuels on March 12, 2012 at 10:19 pm

  Hi.

  I have a clip that contains a long dolly shot that pulls out away from the subject. I now want to remove the dolly track rails from the floor of the shot.

  I’ve painted out the last frame of the shot in Photoshop and imported that back in to AE and everything is looking good (see below)

  How do I now get my new floor to “stick” to my footage (if that makes any sense!?) I’ve motion tracked the shot for position and scale and applied the data to a Null Object. I’ve created a new camera and made the floor layer 3D and tried parenting the camera and floor to the null but it doesn’t have the effect I was hoping. I feel like I’m close but just missing a key point. I found a tutorial on here that deals with object removal but it didn’t deal with a camera movement in Z space. Any ideas where I’m going wrong?

  Thanks in advance for any help anyone can offer.

  

  Ross Shain replied 14 years, 2 months ago 4 Members · 10 Replies
• 10 Replies

• 

  Tudor “ted” jelescu

  March 12, 2012 at 10:33 pm

  Since it is a move that happens in Z space mostly, you need a 3d tracker. Camera Tracker from the Foundry should do a great job. If you do not have budget to buy it now, you can just rent it for this job.
  Once you get the track in place that will give you a camera that moves just like the real camera. You need to position the clean floor in 3d to match the perspective of the actual floor in the shot and then composite that in your shot.

  Tudor “Ted” Jelescu
  Senior VFX Artist
• 

  Stuart Samuels

  March 12, 2012 at 11:16 pm

  Ah ok. I really should have known that!

  I actually have access to Boujou so I’ll have a play around with that and should hopefully get a decent result.

  Thanks.

  Stuart.
• 

  Conrad Olson

  March 12, 2012 at 11:49 pm

  Depending on the camera move you could always try to track the floor in Mocha and use a corner pin to track the floor in place. Looks like an ideal shot for that technique.

  If that doesn’t work then you need to camera track the shot and project your clean frame like Ted suggested.

  —

  conradolson.com
• 

  Stuart Samuels

  March 13, 2012 at 4:28 pm

  Thanks. I’ll give that a try too.

  Once I have my Boujou camera solve imported to After Effects, how do I work with it?
  I’m struggling to find a tutorial that deals with a similar scene to my own.

  Thanks again
• 

  Stuart Samuels

  March 13, 2012 at 7:49 pm

  Hi again.

  I’ve got the relevant info into After Effects from Boujou (I think) but when I pate the position of one of the Boujou track point null objects to my clean floor layer, the floor layer “disappears”. I’ve tried scaling it down and moving it around a bit until I can see it again but I just cant get it in to the right position.

  I’ve been trying all day to work this out and I’m at the point of throwing my computer out of the window (I’m sure most people know how this feels!). I had zero luck with Mocha too. ARGH!!!

  It surely can’t be that of an unusual task but I’ve looked and looked for a tutorial explaining the technique and just cant find one.

  I’ve attached a screen grab from the start of the shot and one from the end so you can hopefully see what I’m trying to do, how I’ve got things set up and the problems I’m having.

  Thanks so much for any help anyone can offer, you just might save my sanity!

  
  Large Image 1.png

  
  Large Image 2.png
• 

  Conrad Olson

  March 13, 2012 at 8:20 pm

  Here is a video tutorial on how to use Mocha for a job like this. I haven’t watched it for a while so don’t remember the details:

  https://library.creativecow.net/articles/larsen_carl/simple25d_rig_removal/video-tutorial

  If you were to use the 3D tracked camera you need to project your clean plate onto the geometry from a static version of your tracked camera, stuck in the position it was at on the the frame that you painted. I stopped using After Effects before I learnt about this technique so I only know how to do it in Nuke

  Here is a quick tutorial showing how to project in Nuke. You might be able to take this technique and use it in AE:

  https://www.thefoundry.co.uk/articles/2009/12/01/97/nuke-production-workflows-rig-removal/

  —

  conradolson.com
• 

  Stuart Samuels

  March 13, 2012 at 8:29 pm

  Thanks so much Conrad. Much appreciated.
• 

  Ross Shain

  March 15, 2012 at 8:42 pm

  If you haven’t solved this yet, I’d be happy to take a look at the file if you can upload it.

  mocha Pro might also be a good option.

  Best,
  Ross

  Ross Shain
  Imagineer Systems
  http://www.imagineersystems.com
• 

  Stuart Samuels

  March 15, 2012 at 9:33 pm

  Thanks, that’d be great. I could only get so far with Mocha and I couldn’t work out how to use the Boujou data effectively.

  Silly question, but where can I upload the file for you to download?
• 

  Ross Shain

  March 15, 2012 at 9:54 pm

  Can you email me at: mocha(at)imagineersystems(dot)com and I will send you FTP upload details.

  Ross Shain
  Imagineer Systems
  http://www.imagineersystems.com

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