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Recently I made another particle trailing effect, but I couldn't get the trailing to produce motion blur.Is it a limitation of OC itself?

It looks like the Tracer elements are created from scratch on each frame in a new location instead of actually moving, so there isn't actually any motion vector data associated with them for motion blur to use. Take a look at them with the Info Channels>Motion Vector kernel. Each particle Trace has no motion vector data. Then try animating the position of the entire Tracer object and you'll see motion data for all its elements.

If the Trace generator object is not moving, then the individual traces it re-creates on every frame are not technically moving either.

So this seems like this is a limitation of the way the Tracer works more than of Octane itself.

Here's a split screen shot of the Info Channel Motion Vecors and your setup, but with the Tracer object animating up and down You can clearly see the motion data. With the Tracer object still, there are zero motion vectors and you get a flat gray image.

You could add the blur in post with either multi-frame blur on a higher frame rate sequence, or with a plugin like Real Smart Motion Blur.

... or it just occurred to me, you can fake it with a texture, since Tracer is actually producing a spline you can sweep a profile down them and apply a ramped opacity material onto it. The C4D docs talk about this briefly under the Motion Graphics Tracer Object section.

Thank you for your answer. In fact, I just think that if there is a simpler way to achieve motion blur of trailing, it will make my future projects more convenient and better-looking (motion blur can often make these trailing more beautiful)

I suddenly thought, if oc can have its own trailing function in the object tag, and can adjust the trailing properties and trailing motion blur directly in oc, would it be a great new feature? I think the trailing function It is also very commonly used in many particle effects or spline animations, although it is not used very often. In fact, I also want to know whether this trailing motion blur is difficult to achieve at the software development level (this is just a personal curiosity about technology)

1026613912 wrote:I suddenly thought, if oc can have its own trailing function in the object tag, and can adjust the trailing properties and trailing motion blur directly in oc, would it be a great new feature? I think the trailing function It is also very commonly used in many particle effects or spline animations, although it is not used very often. In fact, I also want to know whether this trailing motion blur is difficult to achieve at the software development level (this is just a personal curiosity about technology)

Motion blur on normal particles works fine in Octane; it's just this particular way you are creating them with the Tracer that doesn't blur. The C4D Tracer generator completely recreates elements afresh every single frame, so there is no motion in the resulting elements. In comparison, here is a shot of your scene with cubes assigned to the particles instead of a Tracer and they blur as you would expect. Be aware that the Octane Live Viewer doesn't always have all the information it needs to render proper motion blur for individual frames. To check that motion blur is behaving the way you want, it's best to render a couple frames in the Picture Viewer.

frankmci wrote:

1026613912 wrote:I suddenly thought, if oc can have its own trailing function in the object tag, and can adjust the trailing properties and trailing motion blur directly in oc, would it be a great new feature? I think the trailing function It is also very commonly used in many particle effects or spline animations, although it is not used very often. In fact, I also want to know whether this trailing motion blur is difficult to achieve at the software development level (this is just a personal curiosity about technology)

Motion blur on normal particles works fine in Octane; it's just this particular way you are creating them with the Tracer that doesn't blur. The C4D Tracer generator completely recreates elements afresh every single frame, so there is no motion in the resulting elements. In comparison, here is a shot of your scene with cubes assigned to the particles instead of a Tracer and they blur as you would expect. Be aware that the Octane Live Viewer doesn't always have all the information it needs to render proper motion blur for individual frames. To check that motion blur is behaving the way you want, it's best to render a couple frames in the Picture Viewer.

Hello friend, I understand your thinking. In fact, my original idea for publishing this topic was to emit particles. The curved path animation produced by the particles is a video effect that I occasionally use. But I can only use c4d's path tracing to identify these curved animation paths, but I can't give them dynamic blur. It is impossible to achieve a better picture effect. (I don’t understand English, so I translated it with a translator. Please forgive me if the tone is offensive)

1026613912 wrote: Hello friend, I understand your thinking. In fact, my original idea for publishing this topic was to emit particles. The curved path animation produced by the particles is a video effect that I occasionally use. But I can only use c4d's path tracing to identify these curved animation paths, but I can't give them dynamic blur. It is impossible to achieve a better picture effect. (I don’t understand English, so I translated it with a translator. Please forgive me if the tone is offensive)

No, the translation is doing a very good job! There's nothing at all offensive in your writing.

Since the C4D Tracer tool is specifically what you want, I think the option of turning the Tracer paths into geometry using Sweep and a small profile, then applying an opacity gradient texture to that Sweep geometry is your best bet; something like the attached screen grab. In this case I used luminance in a dark environment, but you could use standard diffuse color with an illuminated environment just as well. Keep both your Sweep profile sides and number of Sweep isoparm subdivisions low to prevent things from bogging down with large numbers of particles.

Good luck!

frankmci wrote:

1026613912 wrote: Hello friend, I understand your thinking. In fact, my original idea for publishing this topic was to emit particles. The curved path animation produced by the particles is a video effect that I occasionally use. But I can only use c4d's path tracing to identify these curved animation paths, but I can't give them dynamic blur. It is impossible to achieve a better picture effect. (I don’t understand English, so I translated it with a translator. Please forgive me if the tone is offensive)

No, the translation is doing a very good job! There's nothing at all offensive in your writing.

Since the C4D Tracer tool is specifically what you want, I think the option of turning the Tracer paths into geometry using Sweep and a small profile, then applying an opacity gradient texture to that Sweep geometry is your best bet; something like the attached screen grab. In this case I used luminance in a dark environment, but you could use standard diffuse color with an illuminated environment just as well. Keep both your Sweep profile sides and number of Sweep isoparm subdivisions low to prevent things from bogging down with large numbers of particles.

Good luck!

I understand what you mean, use gradient transparency to blur the surroundings to create a fake motion blur effect, thank you for your communication.