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  • #16
    Originally posted by DADAL View Post
    Interesting stuff joconnell I wish only that Vray would actually re-sample geometry over period of time like we would set long exposure in camera...
    I'm not sure quite what you mean by this - vray does do this resampling over time based on the amount of geometry samples you tell it to use. As far as I know, what it does is look at where the vertices of each mesh in frame 1, then where the same vertices are in frame 2 and make a direction for the motion blur to travel along. If you want to get more samples in the motion blur, vray has to make more copies of the mesh in time so that it can track the movement of the vertices, but again if you're copying the meshes in your scene, it'll take up way more memory - for big scenes or for long animations this might be a serious hit so having control over the amount of time samples makes a lot of sense.

    I tried rendering some long exposure stuff like a light pen writing a word and I had to turn the samples up near to 100 to get a nice clean line!

    You're totally right about your post work though, your renders are stunning so you know exactly how to get the results you want!

    Originally posted by DADAL View Post
    Anyway we can get great results with some post work, check my profile pictures I got aston&bmw with spinning wheels. Neither are fully pushed in quality since they aren't the subject of render but still good enuf for commercial level.

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    • #17
      Originally posted by joconnell View Post
      I'm not sure quite what you mean by this - vray does do this resampling over time based on the amount of geometry samples you tell it to use. As far as I know, what it does is look at where the vertices of each mesh in frame 1, then where the same vertices are in frame 2 and make a direction for the motion blur to travel along. If you want to get more samples in the motion blur, vray has to make more copies of the mesh in time so that it can track the movement of the vertices, but again if you're copying the meshes in your scene, it'll take up way more memory - for big scenes or for long animations this might be a serious hit so having control over the amount of time samples makes a lot of sense.

      I tried rendering some long exposure stuff like a light pen writing a word and I had to turn the samples up near to 100 to get a nice clean line!

      You're totally right about your post work though, your renders are stunning so you know exactly how to get the results you want!

      Hang on, you're saying that if I increase the sample and move light across the screen I will get effect like in night shot with long light trails?

      What about exposure...will it be additive ? or its ignored... ?

      Well will test son to check it for sure heh
      CGI - Freelancer - Available for work

      www.dariuszmakowski.com - come and look

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      • #18
        What I tried doing is making an object with a vray light material and put it on a path using a path constraint. I animated it to travel 100% of the path in 1 frame, then set the motion blur samples to about 100. You get a nice streak! I don't know if vray lights will motion blur, but standard max lights definitely won't.

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        • #19
          Originally posted by joconnell View Post
          I don't know if vray lights will motion blur...
          They should, yes.

          Best regards,
          Vlado
          I only act like I know everything, Rogers.

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          • #20
            Now that is an interesting stuff... will do more blur tests...
            CGI - Freelancer - Available for work

            www.dariuszmakowski.com - come and look

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            • #21
              Here's an image with a sphere with a vray light material animated along a path over 2 frames with frame 1 being rendered. I tried using a vray light instead but the sampling was a bit shitty. Also I tried animating the colour of the vray light material to see if the colour would change over the streak but it seems vray won't do this.

              Click image for larger version

Name:	motion_blur.jpg
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ID:	843766

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              • #22
                Very similar to what I was thinking of testing. Thanks for sharing.
                Last edited by jbeau3d; 01-02-2011, 03:03 PM.

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                • #23
                  Originally posted by joconnell View Post
                  Here's an image with a sphere with a vray light material animated along a path over 2 frames with frame 1 being rendered. I tried using a vray light instead but the sampling was a bit shitty. Also I tried animating the colour of the vray light material to see if the colour would change over the streak but it seems vray won't do this.
                  Not with a material, but animated light color should be fine - see the attachment where I used a sphere light with animated color moving along a path for a hundred frames.

                  Click image for larger version

Name:	sphere_light_moblur.png
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ID:	843767

                  Best regards,
                  Vlado
                  I only act like I know everything, Rogers.

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                  • #24
                    Now that is very interesting... U guys use Vrayphys camera or standard camera?

                    Also I have to go up to 100 subd samples ? It kinda sky rocked by wheel when I pas 20 on geometry...
                    CGI - Freelancer - Available for work

                    www.dariuszmakowski.com - come and look

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                    • #25
                      I used a standard camera; you certainly don't need 100 geometry samples unless your wheel spins insanely fast. For car wheels I would think 6 to 8 would be enough.

                      Best regards,
                      Vlado
                      I only act like I know everything, Rogers.

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                      • #26
                        I have been playing with this same effect for another gig, and actually gave up on the vraycamera blur. It just doesn't seem to behave properly when the shutter speed gets really low, and I needed that for the streakiness.

                        Using the vray camera option in the render dialog is working better for the movement, but I'm getting missing buckets - almost like a DR problem, but the DR is turned off. They move around from render to render.

                        It's also super grainy, even with sub-d set to 100 and geometry samples at 100

                        Any tips?
                        b
                        Click image for larger version

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ID:	843768
                        Brett Simms

                        www.heavyartillery.com
                        e: brett@heavyartillery.com

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                        • #27
                          If you are using the DMC image sampler, try increasing the min. subdivs value to 2 or more.

                          Best regards,
                          Vlado
                          I only act like I know everything, Rogers.

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                          • #28
                            Originally posted by vlado View Post
                            If you are using the DMC image sampler, try increasing the min. subdivs value to 2 or more.

                            Best regards,
                            Vlado
                            That helped with the missing buckets - thanks. Still very grainy though. I think I will probably stick with the animated emitter/facing particle approach I was using before though. It doesn't depend on motion blur at all and is a bit faster to render clean. Lacks some of the look, but I'm still playing with the textures and approach.

                            Click image for larger version

Name:	streaks_particle_shapes3.jpg
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Size:	60.8 KB
ID:	843769
                            Brett Simms

                            www.heavyartillery.com
                            e: brett@heavyartillery.com

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                            • #29
                              Originally posted by vlado View Post
                              Not with a material, but animated light color should be fine - see the attachment where I used a sphere light with animated color moving along a path for a hundred frames.

                              [ATTACH=CONFIG]5806[/ATTACH]

                              Best regards,
                              Vlado
                              Lovely - I stuck with the mesh since I was getting better sub sampling results right away but didn't get around to aa or mb subdivs. Aren't you supposed to be on holidays though

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                              • #30
                                What is your duration setting? Try geometry samples of 10 and play with duration. Set interval center to 0.5.
                                Last edited by scottsch; 03-02-2011, 08:48 AM.

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