Boujou bluescreen track [help]

[Aneks]

Ahhh boujou when it works .... joy ! when it don't..... you're gnerally hosed. Generally when you have frame dopouts that severe over such a long clip you are in for a tough time. To the best of my knowledge in boujou 2.x or similar NO you can't join tracks in boujou. You can export them all out as seperate cameras to your 3d app and then combine them there!!

You might want to try on of the two following things:

Using gold tracks. I generally always use gold tracks even if everything seems to be going right without them. They seem to help solve certain jitter problems.

Try adding a locator or target track on anything that you can identify from frame to frame.
You did place traking markers on you bluescreen right ???!!!

For future reference on of the guys from 2d3 recommened placing scrunced up news paper anywhere on the chroma key that is clear of talent. He reckond that in their tests this was one of best ways to get good feature track results.

Hope this helps !

[mattsmirk]

hi aneks and thanks for your response...

the VFX supervisor did put markers on the bluescreen, little X's, but not enough i guess. the shot is very 'zoomed in/close up' also. although the movement is 'just' a camera pan i never bothered with auto tracking i just did markers which are automatically gold trax i think...

ho hum, i'll have to try something else.... does anyone know of a script to get a track from combustion into 3DSmax6???

cheers,

matt

[joconnell]

The first thing that I found out recently on a shoot is that boujou HATES greenscreen and bluescreen unfortunately. The markers which it needs are one thing but having a completely flat surface to track on doesn't make boujou happy - It needs to have detail at different depths crossing over each other and have plenty of parallax to be able to work out a camera move. A flat blue screen with all of the tracking points on one flat wall is what boujou hates.

You could try using gold tracks but I'm not sure if it'll do it - If you have a nicely arranged grid of tracking points that the supervisor measured that you can recreate in 3d (for exampe if each point was 1 metre apart) then I'd recommend biting the bullet and doing it by hand - you can try wasting time in boujou or you can just get started. You could also try the caera tracker in 3dsmax - it should be okay with something like markers on a blue screen and again if you have measured distances between objects it'll help the accuracy. As another alternative, if it is a close up as you mentioned, you could try rendering out a large plate of your background and then tracking it by hand in after effects and adding sublte tilt and rotation by eye. A bit of dof and motion blur and you'd be surprised what you'll get away with.

Cheers,

John

[beaker]

I have had plenty of luck with Boujou on blue and greenscreen. You just need to set it up right at the shoot. It really likes "T" shaped markers turned on their side pointed away from your subject. Also you want to mark the floor so it can get the depth, not just the back wall. Though that really depends on the shot if you actually have the floor in the shot.

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