3 Replies Latest reply on Dec 29, 2013 6:19 AM by Stephen Barrante

    Particles not moving with Camera as expected.

    Stephen Barrante Level 1

      I have a comp where I'm using a camera I extracted from C4d. The whole setup is just about done, and all of my composited layers, solids, nulls, etc… all match the Camera moves quite well.


      The last effect I wanted to add was just a little "dust and embers" in the air by using either ParticleWorld or Particular. I tried PW first, with all the settings appropriate to create that effect.


      When scrubbing the timeline the particles sway left and right opposite to the camera as the camera pans, as I would expect. But what is NOT working is as I move backwards in my scene (which in this case is along the X axis) they seem to be following the camera move instead of moving opposite to it. This is completely destroying the illusion. I would have thought that as particles are emitted they are essentially in their own 3D space relative to the camera. So any camera in the scene would move towards or away from these in a predictable way. Another way to put it, if it's not clear, is if you were driving your car backwards in the snow, the snow in front of the car would not continue to move towards the car, but fall in place, and new snow would come into view.


      Hoping this is a scale factor, or toggle switch or something dumb. Even more odd is that I am getting similar results if I use Particular. I did, in fact, just try the Snow preset, and it behaved the same way. I feel like I've done this with success in the past, so I'm totally dumbfounded why this didn't "just work". But, alas, that's par.


      Also odd, I have some con-trails coming from a jet flying by and those actually stay put as the camera moves away, they get smaller and move opposite to it. Those are paired specifically to a null that originates from a particular location in the scene. Though moving the emitter to that general spot, just for kicks, did not produce the same results.


      Note, i am not keyframing any aspect of the emitter, as I mentioned before, I just wanted to set it up in place and let the camera move throught the particles.


      I appreciate any help, as I'm very close to wrapping this up!



        • 1. Re: Particles not moving with Camera as expected.
          Rick Gerard Adobe Community Professional & MVP

          Particle systems like Trapcode Particular use the comp center as the center of the particle world. When you extract a camera from c4d then you're setting up a new world center so it's anybody's guess where the comp world center is now. The proper workflow is to export your AE camera and a reference solid or null at comp center to C4D then animate that camera and adjust your objects in the scene in relation to the comp center. This is going to take some planning because the relationship of the particle system center to the camera and the objects in your scene is not linear. You have to experiment. I haven't tried it but you could try extracting lights from the C4D file and use those lights as emitter sources for Particular.


          Particle world is going to be way more difficult.

          • 2. Re: Particles not moving with Camera as expected.
            Mylenium Most Valuable Participant

            Agree with Rick. You probably simply need to straighten out your messy coordinates. As a workaround you may be able to animate Particular's World transform in the opposite direction of your camera move, but it may still look odd.



            • 3. Re: Particles not moving with Camera as expected.
              Stephen Barrante Level 1

              Hey guys, thanks for chiming in.


              One of the first things I did was to straighted out the coordinates of the particle system. And unless I don't understand how they work relative to the camera - which hasn't been my experience in the past - I would have expected them to move appropriately as the camera is moved through the scene.


              I also had tried to set this up in a new comp to eliminate the C4D camera data, so that's not really an issue anymore.


              @Mylenium, yea, I even tried keyframing the opposite camera move by linking the Z-property to the camera's and multiplying it by -1. Lol, unfortuantely that didn't work quite right.


              However, some folks in another forum suggested that the Particle World transform is outdated (as an older plugin) and there are some expressions you can uses on a parented null that may help get everything aligned. Worth further investigation.