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rizon
04-27-2006, 12:10 AM
Damn, it's the first time i use Scene Motion Blur... it took ages and now i see the result i see some ghost fragments of movements in between the frames that make no sence... 1 day of renderfarm for nothing... anyone knows why?

here three following frames
http://www.rizon.be/3d/SMB.jpg

tcastudios
04-27-2006, 12:42 AM
It looks as if you have used only 9 samples per frame. It is almost always to little.
Setting it to at least 16 and check "Antialiasing Restriction" (So Cinema automaticaly turns down antaliasing when not needed, that in turn lessen the rendering time needed) and "Camera Offset".
For faster movement 25 samples might be needed.
But, since there is no real shutter speed involved, each sample is still a snapshot with no smearing of pixels to speak of. These samples are then "simply" multplied on each other, one way or the other.
The next step is doing it in post. Atm with Vixol in separate passes per object (if they overlap) and then RealSmartMotionBlur in AE.
R9.6 have this "Vixol" shader native.

Cheers
Lennart

rizon
04-27-2006, 12:51 AM
thanks Lennart.
But it's already taking 20min / frame on my quad G5... i'll just render it plain and add motion blur in post... i am curious how this "Vixol" shader will do...

tcastudios
04-27-2006, 01:09 AM
Please try a frame set to 16samples and settings as above.
I've done several tests (and posted the results somewhere here) and often 16 render faster than 9 (and sometimes even 5) thanks to the antialiasing restriction.

Cheers
Lennart

rizon
04-27-2006, 01:20 AM
I even set the AA to geometry... so i am not going to take that risk... very narrow deadline... i am doing now some tests in post and it'll work out, maybe just rerendering the close-ups.

But thanks again Lennart... btw i urgently need some time to learn to work with your steadycam...

tcastudios
04-27-2006, 01:24 AM
ok.
I found my post rgarding Smb:
http://forums.cgsociety.org/showpost.php?p=3182241&postcount=5

Cheers
Lennart

rizon
04-27-2006, 01:29 AM
thanks for the test very useful!
concerning the kicking in of restriction that means that AA is set to geometry?

tcastudios
04-27-2006, 01:34 AM
I don't think so (I'm not realy sure). I think it is the (i.e) 4x4 setting that gears down to 1x1.
So basically set all to "Best" etc and Cinema does the rest.

Cheers
Lennart

rizon
04-27-2006, 01:39 AM
just did a test on some new frames, the post really works well... what a relief and renders a lot faster... i thought the overlapping objects would mess up, but all seems fine.... + still control over it...

this weekend i am going to try the vixolshader, i was wondering, the pass you render out for the reelsmart motion blur, do you need to rerender the whole scene or can i just for instance make all objects just simple grey and just create the pass.

tcastudios
04-27-2006, 01:53 AM
To make a long story short. The task of rendering out each object (because of overlapping)
with its own complete alfa (Object buffer don't cut since parts of each object will have incomplete alfas), keeping track of each Vixol pass and then put together the zillions of layers correctly, is simply not worth it with scenes that don't have more than a few objects happening.

Also if any object are revolving, hiding itself, Vixol/RealSmartBlur won't work.

If no very special effects are needed, most often the Cinema Smb works fine and takes less time all in all to finish.

It looks as if this might change somewhat with the new object mask option in 9.6. But I know nothing of that yet.

Cheers
Lennart

LucentDreams
04-28-2006, 10:35 PM
the frame in question looks more like an issue with interpolation in the subframes. look at your rotation data carefully at that one point does the rotatiosn suddenly flip aorund in values on any axis?

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