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[doka15]

I finished my first track and I used Cinema 4D and AE to finish it. There is a little slippage with the rock on the street. What is the process of going back to fine tune the track to resolve this slipping? Also what would cause it since the rest looks pretty good?

http://www.sbtraveler.tv/flicks/web_rock.mov

Thanks,

-Lars

[gordonrobb]

Lars, look good to my, can't say that I can see the slippage. However, I normally find that if there is slippage, but you feel you have a good solve (what is your Hpix error score?), then it is most likely that the CG element is not placed on the ground accurately enough.

[doka15]

Thanks for the reply. I guess I am just super picky when it comes to a solid track.

I re rendered out the rock with motion blur this time around to give it a better look. In Cinema 4D I used the multi frame rendering where it renders 5 frames and the merges them together to give it a more natural blur.

But now there is even more slippage. If you load the new version and then press the arrow key 7 times to advance the qt movie, you will see the first jump of the rock. I know it is rendering 5 sub frames between frame 6 and 7 to get the blur.

http://www.sbtraveler.tv/flicks/rock_miltipass.mov

I don't know what is causing this? Has anyone else had this type of problem?

Thanks.

-Lars

[ShadowMaker SdR]

It looks like the render and the movie are 1 frame out of sync, because the jump you describe is there in the next frame. So if you'd make rock frame 6, correspond with background frame 7 I think things might be better already.

[basti]

no, there's no frame shift - it would slide much more.

the problem might be autotracking (manual tracking is way more precise!).
you'll have a fun time finetuning your autotracked shot because of the
enormous number of tracks. so always use manual tracking

and there's a big problem regarding c4d's scenemotionblur.
it's the only 3d tool on the market which is sampling the motionblur
between the current frame and the next (correct mb-sampling
would be between previous, current and next frame).
that's why it looks even more out of sync when using scenemotionblur.

workarounds would be to use vectormotionblur (activate "open
shutter at frame") or move the entire animation a few subframes
forward if you want to stick with smb - which i'd definitely prefer.

basti

[doka15]

Shadow maker: That is what I thought too that the it wasn't landing on the same frame. Also when you export a lightwave scene there is the button bellow on the export window that asks frame 0 or 1. When I did try to offset it in After Effects it was way off.

Basti, What you said sounds right and I know that but I never thought about it, thanks. C4D is rendering between frame 6 and 7 to get the motion blur but C4D is guessing what frame 7 would be. In real world frame 7 isn't shot yet so C4D is pre geussing what is happening and that is cauing the problem. I see what you are saying now.

I will try the motion vectoring like you suggested!

Thanks much!

-Lars

[gordonrobb]

Doka

This second shot is far worse than the first. Two things to check.

When you watch the shot in SE, do the trackers move slightly against the shot (especially where you think you have a proble). If they do, your solve is not good enought for you.

Or.. Have you checked that the block is where it needs to be? The first shot looks like a very slight sliding problem (although I mean very slight) which is almost always about CG placement (I think).

What is your error size in SE?

[basti]