View Full Version : 3D Tracking Problem (Student)


Waterfronts
07 July 2008, 02:10 AM
Hey I'm a student at VFS and I'm having a real hard time tracking it. I'm using Boujou and I have no instructors at my school who know how to use it even though were supposed to get taught it. So I'm having to resort to people outside of my school. I have linked below the shot I'm trying to track. Its a dolly pan camera move and I just cannot get the solves I need, nothing is working. I've masked out everything that moves, which is a lot, and I've even put in locators and target tracks ontop of the normal feature tracks. I've tried specifieing out of all the feature tracks which ones I want boujou to solve with by making them gold tracks. I've put in all kinds of planer constraints and resolved and ajusted for camera distortion and camera path smoothness. I've tried everything I can think of and watched evry tutorial I could get my hands on but I haven't been able to get a good solve out yet and I've been solving for about 2 weeks now and I'm very frustrated and getting kinda depressed and running out of time. I've heard you can't get a perfect solve this kind of camera move, I've heard your supposed to get it close and then hand animate it in post. But I'm havig problems even doing that. So if ANYONE has any comments, suggestions or things to try or even past work experience with this that they could share it would be greatly appreciated!

This is the link to my shot:
http://student.vfs.com/~3d71manley/Dolly_Pan.mov

This is a one of the best tracks I have so far:
http://student.vfs.com/~3d71manley/blast4.mov

Ralphy
07 July 2008, 03:15 PM
Looks like you're getting pretty close.
If the only thing that you're adding in 3D is the building, then I would focus my gold tracks on the building itself. Secondly, make sure you use the "join" function for the tracks that get split up as the light pole passes in front of the building. Click on one track, wait until the pole causes it to fail, then shift click on the track that pops up on the other side in the same position and click "join". Boujou will treat this as one long feature track when it does it's calculations.

Also, if you're only tracking for the building, then don't bother tracking the entire shot. Just work on the section that you need.

If all else fails, I'd recommend reversing your plates in some compositing or video editing software so that the sequence runs backwards. Boujou doesn't like things popping in from the sides as the camera travels in reverse - so if you reverse the plates, then there is a bit more forward movement, which boujou likes.

blurgh
07 July 2008, 12:39 AM
Hey dude,
unfortunatly not every tracking app is suited to every shot.. some just wont do a great job no matter what.
However I would certainly try everything that Ralphy suggests especially about only tracking the building part of the shot..

also as part of reversing the foothae.. it might be worth playing around with brightnesds and contrast etc so that boujou can pick up more.

it looks liek you have a few tracks on the buildings in the really far distance around frame 382.. this can screw up the depth as it just cant calculate far enough away.. its hard to see what your tracks on the cars at the end are doing, but keep a close eye on them as shiney and transparent materials can cause a lot of issues (with auto tracks)

in terms of adding tracks.. id have a go at getting more in the foreground.. like on the corener of the white lines on the floor around frame 244 and the lamp post and newspaper dispencer things from 369ish - around 508ish


If you were to try and fix it in post.. the basic procedure would be to bring the camera into maya (or whaterver your 3dapp is) put the camera group under a locator and animate on the locator. ( its hard to tell o nthe video how good or bad the building is, but if its slifing off in a relatively smooth movement you can often fix it with only a few keys...

out of interest have you got film backs and lens data? what ever data you can provide should help the solution

Waterfronts
07 July 2008, 01:53 AM
Hey Ralphy,

Thank for the advice, I didn't actually know about the join tool, thats awesome. Unfortunately it didn't help a whole lot. I actually am now tracking in PFTrack, which is working a lot better for me so far, but we'll see. I think I've exhausted boujou to the best of my abilities. And no I'm not just comping in the building below is another link to the bigger scale of what I'm doing. Everything is still not in there, I have a bunch more high rises to put in and bins fire hydrants and I plan on keying some people in via green screen.


This is the link to the playblast of the new track from PFTrack:

http://student.vfs.com/~3d71manley/TestBlast_B.mov


Looks like you're getting pretty close.
If the only thing that you're adding in 3D is the building, then I would focus my gold tracks on the building itself. Secondly, make sure you use the "join" function for the tracks that get split up as the light pole passes in front of the building. Click on one track, wait until the pole causes it to fail, then shift click on the track that pops up on the other side in the same position and click "join". Boujou will treat this as one long feature track when it does it's calculations.

Also, if you're only tracking for the building, then don't bother tracking the entire shot. Just work on the section that you need.

If all else fails, I'd recommend reversing your plates in some compositing or video editing software so that the sequence runs backwards. Boujou doesn't like things popping in from the sides as the camera travels in reverse - so if you reverse the plates, then there is a bit more forward movement, which boujou likes.

Waterfronts
07 July 2008, 02:10 AM
Hey Darken-R

Ya I've played with the contrast and brightest and yes it does help with the track and the reversing of the track happens automatically in PFTrack but I haven't tried reversing in Boujou, maybe I will if I can't get anything soon. Ya I've tried tracking the buildings in the background and I've tried masking them out as well both with not so good results. But Yes I would agree with getting more track up close, I'll try the crosswalks for sure. Ya I'm using maya and thank for that tip, I didn't think of it doing it that way. I was thinking actually of doing it in Nuke with just a transform node. What do you think of that idea?


Hey dude,
unfortunatly not every tracking app is suited to every shot.. some just wont do a great job no matter what.
However I would certainly try everything that Ralphy suggests especially about only tracking the building part of the shot..

also as part of reversing the foothae.. it might be worth playing around with brightnesds and contrast etc so that boujou can pick up more.

it looks liek you have a few tracks on the buildings in the really far distance around frame 382.. this can screw up the depth as it just cant calculate far enough away.. its hard to see what your tracks on the cars at the end are doing, but keep a close eye on them as shiney and transparent materials can cause a lot of issues (with auto tracks)

in terms of adding tracks.. id have a go at getting more in the foreground.. like on the corener of the white lines on the floor around frame 244 and the lamp post and newspaper dispencer things from 369ish - around 508ish


If you were to try and fix it in post.. the basic procedure would be to bring the camera into maya (or whaterver your 3dapp is) put the camera group under a locator and animate on the locator. ( its hard to tell o nthe video how good or bad the building is, but if its slifing off in a relatively smooth movement you can often fix it with only a few keys...

out of interest have you got film backs and lens data? what ever data you can provide should help the solution

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