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Gorf · Joined: 10 Mar 2007 Posts: 111

I've tracked and solved my footage, exported it to my 3D package then worked on the scene without too much messing about. Everything looked OK so I started the render in "final" mode and went to bed. Nothing too surprising so far.

When I looked at the composited film, there was a three-frame "blip" where it looked like my model briefly disappeared into hyperspace.

It seems that when the camera goes through the 0 degree mark (at least in the Y axis, probably all of them) it does not continue through zero to the next positive (or negative) valie, it jumps back to the 360-ish value on the same side of zero.

Sorry if my non-technical description is making it more confusing than it needs to be. The footage I tracked is a camera doing a complete circuit of a crater. The co-ordinate system I applied is fairly arbitrary, but as the flat ground is outside the crater, that's where the three features that define the ground plane are. The camera's Y rotation was coming up towards zero in about 0.4 degree steps, but instead of going from -0.35 to +0.05, it went to -359.95. Mathematically, that's no big deal, as long as your render is only doing one pass per frame. I'd set my render to work in multiple passes per frame, so the schizoid camera _between_ -0.35 and -359.95 really showed up.

Is there any way to smooth this out during the export, or is it something I always have to watch out for, and fix in the animation software?

ssontech · Posted: Sun May 20, 2007 3:40 pm Post subject:

What package is that? It might be that the exporter should take a counter-measure, or maybe in the animation package (for example, changing the type of keying or interpolation used). Note that you can also look in the exported file to see what's what.

Gorf · Joined: 10 Mar 2007 Posts: 111

It's Hash Animation:Master.

Once I realised (with the help of the Hash forum members) that it was the camera, not my model, that was causing the problem, it was easy to see how to fix it in a:m.

I didn't know what I was looking for at the time. A near-360 degree shift is easy to spot, and correct, once you know the effect - and I'm not sure SynthEyes should be trying to fix such situations - If it did filter such huge changes, surely that would be bad for users who need big changes in their camera placement?

Anyway - I'm done with this footage for now - the result is here. When I can, I'll replace the floating landspeeder with something that actually touches the ground and might give some inkling of slippage if the tracking solution is no good.