rendering with motionblur is 15 times slower

[FSGFX]

is this really possible... or is there something wrong in my scene.?
i rendered a lot with motionblur in the past and never had a slowdown like this.


there is nothing special in this scene.
adaptive subD 1/4
sinc filter
BF BF 16

[georgi.zhekov]

Hello,

Is it possible to send us a scene so we can take a look if there is something wrong?

Best regards,

[FSGFX]

sorry not this one... NDA...

i tried now to use a point cache instad of the rigged version...
and its faster now... not really fast but faster... could a rig cause such issues..?

[ivaylo.ivanov]

The renering speed depends on the size of the motion blur. Compare the number of raycasts (written in the Output Window) with and without mb. If they are 15x more, it's normal to render 15x slower

[FSGFX]

is there a way to see how much raycasts are needed to render the image.`?

[FSGFX]

found it...

no motionblur
[2015/Mar/24|13:18:29] V-Ray: Number of raycasts: 164099848
[2015/Mar/24|13:18:29] V-Ray: Camera rays: 3067193
[2015/Mar/24|13:18:29] V-Ray: Shadow rays: 145999075
[2015/Mar/24|13:18:29] V-Ray: GI rays: 20920299
[2015/Mar/24|13:18:29] V-Ray: Reflection rays: 4748623
[2015/Mar/24|13:18:29] V-Ray: Refraction rays: 0
[2015/Mar/24|13:18:29] V-Ray: Unshaded rays: 0
[2015/Mar/24|13:18:29] V-Ray: Number of intersectable primitives: 40478
[2015/Mar/24|13:18:29] V-Ray: SD triangles: 6
[2015/Mar/24|13:18:29] V-Ray: MB triangles: 0
[2015/Mar/24|13:18:29] V-Ray: Static primitives: 40470
[2015/Mar/24|13:18:29] V-Ray: Moving primitives: 0
[2015/Mar/24|13:18:29] V-Ray: Infinite primitives: 2
[2015/Mar/24|13:18:29] V-Ray: Static hair segments: 0
[2015/Mar/24|13:18:29] V-Ray: Moving hair segments: 0
[2015/Mar/24|13:18:29] V-Ray: Total frame time 0h 1m 58.8s (118.8 s)


with motionblur
[2015/Mar/24|14:06:04] V-Ray: Number of raycasts: 1650097277
[2015/Mar/24|14:06:04] V-Ray: Camera rays: 15619566
[2015/Mar/24|14:06:04] V-Ray: Shadow rays: 1490565799
[2015/Mar/24|14:06:04] V-Ray: GI rays: 200218296
[2015/Mar/24|14:06:04] V-Ray: Reflection rays: 17918126
[2015/Mar/24|14:06:04] V-Ray: Refraction rays: 0
[2015/Mar/24|14:06:04] V-Ray: Unshaded rays: 0
[2015/Mar/24|14:06:04] V-Ray: Number of intersectable primitives: 124122
[2015/Mar/24|14:06:04] V-Ray: SD triangles: 6
[2015/Mar/24|14:06:04] V-Ray: MB triangles: 0
[2015/Mar/24|14:06:04] V-Ray: Static primitives: 2034
[2015/Mar/24|14:06:04] V-Ray: Moving primitives: 122080
[2015/Mar/24|14:06:04] V-Ray: Infinite primitives: 2
[2015/Mar/24|14:06:04] V-Ray: Static hair segments: 0
[2015/Mar/24|14:06:04] V-Ray: Moving hair segments: 0
[2015/Mar/24|14:06:04] V-Ray: Total frame time 0h 46m 19.0s (2779.0 s)

[FSGFX]

with motionblur but no reflections
[2015/Mar/24|14:52:29] V-Ray: Number of raycasts: 1330255848
[2015/Mar/24|14:52:29] V-Ray: Camera rays: 14888094
[2015/Mar/24|14:52:29] V-Ray: Shadow rays: 1232010590
[2015/Mar/24|14:52:29] V-Ray: GI rays: 181286359
[2015/Mar/24|14:52:29] V-Ray: Reflection rays: 0
[2015/Mar/24|14:52:29] V-Ray: Refraction rays: 0
[2015/Mar/24|14:52:29] V-Ray: Unshaded rays: 0
[2015/Mar/24|14:52:29] V-Ray: Number of intersectable primitives: 126964
[2015/Mar/24|14:52:29] V-Ray: SD triangles: 6
[2015/Mar/24|14:52:29] V-Ray: MB triangles: 0
[2015/Mar/24|14:52:29] V-Ray: Static primitives: 2118
[2015/Mar/24|14:52:29] V-Ray: Moving primitives: 124838
[2015/Mar/24|14:52:29] V-Ray: Infinite primitives: 2
[2015/Mar/24|14:52:29] V-Ray: Static hair segments: 0
[2015/Mar/24|14:52:29] V-Ray: Moving hair segments: 0
[2015/Mar/24|14:52:29] V-Ray: Total frame time 0h 29m 42.5s (1782.5 s)


no motionblur no reflections
[2015/Mar/24|14:56:56] V-Ray: Number of raycasts: 70330163
[2015/Mar/24|14:56:56] V-Ray: Camera rays: 2865609
[2015/Mar/24|14:56:56] V-Ray: Shadow rays: 62888401
[2015/Mar/24|14:56:56] V-Ray: GI rays: 14072465
[2015/Mar/24|14:56:56] V-Ray: Reflection rays: 0
[2015/Mar/24|14:56:56] V-Ray: Refraction rays: 0
[2015/Mar/24|14:56:56] V-Ray: Unshaded rays: 0
[2015/Mar/24|14:56:56] V-Ray: Number of intersectable primitives: 40034
[2015/Mar/24|14:56:56] V-Ray: SD triangles: 6
[2015/Mar/24|14:56:56] V-Ray: MB triangles: 0
[2015/Mar/24|14:56:56] V-Ray: Static primitives: 40026
[2015/Mar/24|14:56:56] V-Ray: Moving primitives: 0
[2015/Mar/24|14:56:56] V-Ray: Infinite primitives: 2
[2015/Mar/24|14:56:56] V-Ray: Static hair segments: 0
[2015/Mar/24|14:56:56] V-Ray: Moving hair segments: 0
[2015/Mar/24|14:56:56] V-Ray: Total frame time 0h 0m 40.5s (40.5 s)

[FSGFX]

new test...

same scene...

simple sphere with glossy material
sphere only --> 12 sec
sphere + moblur --> 2min
sphere + subD (max 4) --> 4min

[FSGFX]

ok found the issue...
i rendered all the other scene with the adaptive sampler...
but somehow i turned on the "adaptive subd" in this scene... and that causes those insane slowdowns...