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VFX Guide Lesson 12 Practice Exercise Question For Experts

PostPosted: Mon Mar 04, 2024 12:34 am
by Sean Weaver
Can someone at BMD (or an expert on this forum) help sort out the last question I had at the end of Lesson 12 please?

To keep this really simple, organized, and to the point, here is a Dropbox folder containing the .dra, a separate export of my .comp from the exercise, and the VFX Guide .pdf : ... hmfe2&dl=0

The question/issue involves values on Camera3D1 after Export from the CameraTracker, after creating the mattes for the areas I wanted to avoid.

The BMD completed one is in the Lesson 12 Completed timeline. The one I worked on is under Lesson 12 Start. In the comp I tried to keep things clear. On the left side is a series of nodes containing a set of mattes that was not keyframed, so it drifts off the subjects. THIS is exactly what I found BMD did in the Completed timeline. But it's not what I originally did....

Because previously we had keyframed everything throughout the .comp, I went ahead and rotoscoped everything like usual, and when I got done and performed the Export, things were very weird. The flag seemed to move and never looked tacked down to the rocks. Things were generally off. Looking closer, the Far value under the Camera3D1 node was low - as in, sixty-six.

But when I didn't keyframe at all the way that the Completed timeline from BMD has no keyframe on the mattes....the Far value was 1078 and everything looked much better.

Digging deeper into the Reference Manual born out of complete and utter frustration and despair with the holes and omissions throughout the VFX Guide, at least I did learn a little more about the Camera3D near/far values.

But I'm still very unclear on what is shifting the value that much just because I adjusted the mattes throughout the render range vs. a sloppy few mattes that are not but somehow....that's what in the BMD completed timeline and what seems to work better in this case.

And I'm also not entirely clear on why if I copy the ImagePlane3D node from the completed timeline into my .comp in the Lesson 12-Start timeline, things don't line up with the transform values and the banner doesn't look as good as it does in the Completed suspicion is it may have to do with the Ground plane settings.

My computer is slow and laggy to work with the practice files anyhow in this 3D exercise and I'm not about to buy a new computer in the immediate future, and whether or not I even need to do 3D Camera Tracking at all for guitar videos seems unlikely.

But after the process I just went through for weeks (and it was excruciating) chronicled in the other thread containing all the typos and omissions, I'm not about to let the last Practice Exercise defeat me.

So what's going on here? What did I miss? Or what else was not stated in the guide that affected the outcome?