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View Full Version : How can I create a trailing light effect?



alexjose
11-28-2017, 02:02 PM
I have a realistic earth scene and would like to do something like a trailing light, kind of like a comet, on a lens flare that passes through the scene. I have no idea how I'm gonna do this. I've tried motion blur on lights/objects parented to the light but it doesnt create a good effect. I'd like to be able to control the length of the tail with something like an envelope (I guess I could do this with motion blur) but when using motion blur on anything over about 3000% it looks like just far spaced dots instead of a tail. I'd also like it to be thicker near the lens flare and thinner the farther it goes back. Any suggestions? Thanks

MonroePoteet
11-28-2017, 02:11 PM
Here's a recent thread on tracing planetary orbits that might be useful:

http://forums.newtek.com/showthread.php?155149-How-to-reveal-a-trace-along-a-path

and here's my post on using Particles and HV's to do so with a sample scene:

http://forums.newtek.com/showthread.php?155149-How-to-reveal-a-trace-along-a-path&p=1523796&viewfull=1#post1523796

mTp

alexjose
11-28-2017, 02:52 PM
Thanks! That looks like exactly what I'm looking for. I tried it out but my particles arent showing up for some reason. I used the same properties as you mentioned in the post ...

"The basic idea is to put a Null on the trailing edge of the Planet's diameter, add an FXEmitter in the Properties=>FX tab, have it emit 60 Particles per second (2 per frame, more if needed depending on the speed and radius of your orbit), make sure the FXEmitter etc=>Parent Motion is set to 0%, the Life Time is 0% (they don't vanish over time), and the Resistance is set to 10.0 so they stick right where they're emitted.

Then, the Hypervoxels are tuned to the scale of your planet / scene, give whatever color you want. In this scene I used Sprites, turned off all Lights so the planet doesn't cast a shadow on the trail, and set the Luminosity to 1000%."

but theyre just not showing up. (See attached images) I am using lights in the scene but I turned all the shadows off and turned all the lights off too and still cant see anything. This is my first time using particles and HV so I'm not sure if I'm using them right. The Null object is the object that orbits the planet and emits the particles, hopefully I set everything up right. 138696138697138698138699

MonroePoteet
11-29-2017, 08:16 AM
It looks like your HVs are 10mm in size, which is really tiny. Unless your planet object is also very tiny, you need to vastly increase the size of the HVs. In the sample scene I posted, I think they were 500 *meters* in size.

mTp

alexjose
11-29-2017, 09:12 AM
Yeah My planet is only about 4.5 m in diameter. I tried different sizes with the HV to no avail

prometheus
11-29-2017, 09:17 AM
Yeah My planet is only about 4.5 m in diameter. I tried different sizes with the HV to no avail

then it might not be it then, but for checking the hypervoxels particle size, check the "show particles" in the hypervoxels geometry tab so you can see your size in the opengl before rendering, and adjust scale so you clearly can see itīs there.
maybe you havenīt set particle limit high enough, and if you try to render a frame a bit in the scene, it runs out of particles?
Also reset your motion blur settings so that isnīt interfering.

alexjose
11-29-2017, 09:33 AM
Thanks, I do see the particles in OpenGL and have them set to about 45 mm but they don't show up when I render for some reason. Im not sure what other setting configuration it could be

alexjose
11-29-2017, 10:08 AM
I just borrowed MonroePoteet scene from his zip file (hope he doesnt mind) and put my planet in it and customized it and its working well now. Not sure what my problem was

MonroePoteet
11-29-2017, 12:25 PM
No, I post sample scenes so people can use them and hopefully learn from them. From the screen shots you posted earlier, it also looks like you didn't disable the Light and crank up the Luminosity as I did in my scene, and so the HVs would be in the shadow of the planet and might have been overwhelmed by the Lens Flare. Dunno.

mTp