Trapcode Particular Question

[bradk40887139]

Hey everyone,

Hoping someone on here is well-versed in Trapcode Particular - I'm having trouble keyframing Particles/Sec within Particular. It seems like that whatever the first value I have set for the particles, that value is what stays for the whole effect, no matter what I try to keyframe differently later. For example, for the first pair of screenshots, I started off with 20,000 for Particles/sec, and then several frames later, I keyframed it to 60,000, but as you can see, the number of particles on the screen stayed exactly the same. Then I did the exact opposite in the next pair of screenshots, starting at 60,000 and going down to 20,000. Looking at that second keyframe, the number of particles on the screen stayed at 60,000 even though it says it's 20,000. Whatever the value is when I start keyframing, that is the value that stays no matter what number I type in.

Does anyone know why I can't keyframe different values of particles/sec within Particular? Seems like an issue that shouldn't even exist, any help would be awesome! Thanks

[Dave Merchant]

You are changing the birth rate of particles, not how many are 'on screen'. Until the existing ones die, they stay put.

[David Arbor · Accepted solution]

According to your timecode your keyframes are only 4 frames apart. The setting is particles/second, which means that from the time of the new KF Particular will generate 60,000 particles per second. You're changing values in less than 1/8 of a second, so that's not going to give the effect you're looking for. What's the lifespan of your particles? Are they also dying too quickly? Your emitter mode is set to Continuous, and that's not keyframeable, so if you're going for a burst you can try exploding that number to something crazy high, if that's the effect you're trying to achieve.

[Mo Moolla]

davidarbor​ "Your emitter mode is set to Continuous, and that's not keyframeable, so if you're going for a burst you can try exploding that number to something crazy high, if that's the effect you're trying to achieve."

Fully agreed

[bradk40887139]

Thanks guys, much more clear now - appreciate it.

[neuromancer_mad]

For me works fine keyframing particles/sec in continuous mode. You can start and stop emitting particles in the timeline, and works fine if your solid starts at keyframe "0". Exploding mode is useless in some situations, keyframing continuous mode usually is the best and easy way to control when and how much particles birth per second increasing or decreasing gradually.

[Mylenium]

There is no issue. You are just not understanding that you are keyframing the base emission rate, not the overall number of particles. After only a couple of frames and the other parameters defined this may not at all give any visual difference at all. that and even if it did, those changes might be minute and not be discernible, only affect off-screen, already dead or almost transparent faded (and thus nearly invisible) particles and a million other things. It seems to me you need to spend some time trying to work up a basic understanding of how Particular works or lifespan-based, dynamically evaluating particle systems in general. None of this is unusual, you just have wrong expectations of hoiw you want it to work vs. how it actually works. All those theoretical considerations aside, there is usually not much point to keyframing emission rates for the type of stuff you seem to be after. It would probably be more efficient to create more emitters and use layer duplicates with Particularls unified 3D rendering. Turning on and off emitters/ fading layers to control densities will be much easier than trying to predict the behavior of the overall lifespan evaluation as you just found out the hard way.

Mylenium

[bmartin219]

I'm actually having this same issue. Seems that if I have my emitter on continuous, let's say 500 particles/sec, if I keyframe that to 0 particles/sec 1 sec, 5 sec, 10 sec later, it just never stops. Same thing if I try and do the reverse, it only reads the first keyframe. 

Any insight would be great - thx!

Edit - it worked for a sec (keyframing several seconds later to 0, and now trying to repeat it's giving me the same problem)

Here is a Youtube link of me demonstrating the problem - 

https://youtu.be/tdqr18MWxuI

[bmartin219]

Bumping this thread. Anyone have any insight on tbis? Is this thread dead now because there is a correct answer/should I start a new one?

[Ethan Clarke]

I'm having the same problem.  I've been using particular for years.  I've alway been able to keyframe a continuous birthrate.  Now I have a new imac (not M1 chip) and upgraded aftereffects. Now it only sometimes works when I go to "turn off the flow" of particles by keyframing birthrate.  The change doesn't occur until way down the timeline.

If I change emitter behavior to explode, I only get the particles that are created on that first frame.

Using: Mac OS big sur. AE 18.2.1, Trapcode suite 16

[neuromancer_mad]

For mi works fine. But there are some considerations, your solid with particular must start in frame 0, you can move the keyframes whereever you want in the timeline. If you displace your solid in timeline, will work, but the particles will not be emitted at the keyframe but later in the timeline.

[derekk89728850]

Did you ever get your keyframes working? I'm having the same issue here.  Glad I'm not the only one.  Seems I've tried everything at this point.  I've used particular for years in my projects.  Now when I go to keyframe properties it doesn't work.  Must be a new glitch. Unfortunately, I bought v16 in January so I missed out on the v17 update.  Did anyone figure this out.  It's incredibly frustrating and I'm trying to finish up a paying job right now.  Any help would be much appreciated.

[anders_hattne]

I found that having the layer that has particular starting anywhere but at frame 0 causes a bit of a problem -
just like linking layers in preComps with valueAtTime when the different compositions start at different times.

Not sure if that is the problem here, but in my case, having the layer inPoint at frame 0 and start keyframing at say frame 100 worked, rather than starting the layer at frame 100..

[Ethan Clarke]

Yes.  Starting at frame zero worked.

thanks gang

[danielr88672531]

Thanks. Finally!