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Simon Wicker
11-27-2005, 07:34 PM
i have seen some examples of the new FR motion blur and they all look very good - however to be able to integrate into a film vfx pipeline i would need the ability to match shutter timing between the various apps (i.e. whether the blur is centered around the frame or whether it occurs between frames). does anyone know if FR has a control for adjusting this - the latest cinema has a switch for this in the vector motion blur which is good, but the actual quality of the vector blur is not up to renderman standards.

cheers, simon w.

Chrissyboy
11-27-2005, 07:40 PM
Hi Simon - someone in the cebas forum was kind enough to post some interface screenshots, and from the look of the Camera pane here (http://www.pixiemedia.com/fc4d/divers/screens/6.gif) I'd guess that 'phase' is the setting you're looking for, I imagine that 0-100% would equate to entirely pre- or post- shutter.

Still waiting for the Mac version to be able to know for sure...

Cheers - Chris

i have seen some examples of the new FR motion blur and they all look very good - however to be able to integrate into a film vfx pipeline i would need the ability to match shutter timing between the various apps (i.e. whether the blur is centered around the frame or whether it occurs between frames). does anyone know if FR has a control for adjusting this - the latest cinema has a switch for this in the vector motion blur which is good, but the actual quality of the vector blur is not up to renderman standards.

cheers, simon w.

Simon Wicker
11-27-2005, 09:05 PM
hi chris,

thanks for the link to the screenshots - if my rusty memory of the cinema vmb serves then the phase determines where the blur is centered physically (i.e. whether the object is blurred to the left or right or about its center) but cebas also need to implement the 'open shutter at frame' checkbox.

this means that if we are rendering frame 10 when can determine whether the shutter is open from frame 9.75-10.25 or frame 10-10.5. you would then further refine this using phase to set whether the motion blur trail is to the left or right of the object.

to be perfectly honest i have never understood why there is a phase at all - in my mind the blur is calculated centered on the object.

cheers, simon w.

bobtronic
11-27-2005, 09:14 PM
to be perfectly honest i have never understood why there is a phase at all - in my mind the blur is calculated centered on the object.

the phase is very useful for still images, for example to render nice motiontrails that lag behind the moving objects.

Bob

Per-Anders
11-27-2005, 09:46 PM
if you don't use the prepass then you only get a straight motion blur (with the option of a trials mode), with a prepass you can then also control the duration of the motion blur and the phase to shift it's focal point (to set it between frames if that's what's wanted). the motion blur is a 3d motion blur, not a vector motion blur so the results are great but it's very fast and smooth (unlike smb in c4d).

chris_b
11-27-2005, 09:54 PM
Hello Simon, here is a quote directly from the fR2 manual... maybe it helps clarify:

"Phase - in a real camera the motion blur effect is always centered (50%). However, the Motion Blur effect within finalRender can be altered, and the blur effect can be biased. You can move the center of the motion blur effect towards or away from the current frame. For realistic effects, keep it at 50%."

Perhaps some comparative renders will show whether the algorithm calculates with the shutter open at frame or not? Either way, the quality is definitely better than the built-in vector blur, which exhibits some really bad artifacting even on simple scenes in my experience, and much faster than scene, which is nuts to use on anything but the most simple scenes. Exciting that we do have a real 3D blur option!

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