What are the differences between After Effect particle simulator vs Hitfilm particle simulator?
My gut says the number of folks on this forum who know both AE and HitFilm to that level is very small, which may be why you haven't received an answer yet.
My first question (and this is a genuine question, not something snarky) is: why do you want to know? What will knowing the differences between the two particle systems do for you? If (and this is just a wild guess) you're watching AE tutorials that use particle effects and want to know if/how the same effect could be done in HitFilm, you might get a better response by pointing to a specific effect and asking how that could be done in HitFilm. It's often easier to help with specifics than broad generalities.
@jsbarrett Actually I (and a few other people) probably do know both programs well enough to answer this question.
Problem is, to answer in detail would take a REALLY long time and be a REALLY long answer--and that's coming from me--someone who's overflowed the maximum word length for this forum's posts (I bet you didn't even know there WAS a work limit!), and I really don't want to get into it.
Long story short, CC Particle World, the built-in particle sim in AE is nowhere near as powerful as the particle simulator in Hitfilm. Hitfilm has more emitter options, more texture options (like 3D models), more animation options, more physics options and, in general, many more options and complex behaviors possible in absolutely every way compared to CC Particle World. The ONLY thing a Hitfilm user would miss from particle world is you can feed it a text object and tell it to fire that text object one letter at a time.
Now, if Andersen is referring to the particle simulator seen in the majority of Ae tutorials online--that's Trapcode's Particular, which is a $400 plug-in for Ae. Well, with version 3, Particular finally caught up to Hitfilm in some ways, passed Hitfilm in a couple of others, and will never catch up to Hitfilm in a couple of respects. Particular can FINALLY use 3D models as textures, can FINALLY have more than a single emitter/system in a single layer, but STILL can't have more than one deflector. Particular's turbulence looks a little nicer and can be used for a couple of effects looks Hitfilm's can't because particular's turbulence is really a fractal displacement while Hitfilm's is a motion randomization. Overall, however... yeah, Hitfilm's is more powerful.
Both Particle World and Particular are (in Hitfilm terms) always rendered as 2D layers, so getting a Particular Layer to interact with anything else in 3D space is a pain.
Hitfilm and Particular both let one create emitters. Those emitters can take various shapes and emit particles in different trajectories. Both can emit particles that emit their own particles--in Hitfilm that's a Mobile Emitter, in Particular that's an Aux Particle. Both can use built-in textures, or the contents of a photo/video layer or a 3D model as a particle texture. Both have gravity/wind and turbulence. Both have deflectors. Both have ways of giving particles more individual motion--Hitfilm's Lifetime Panel or Particular's Life over Time (now "Curves") graphs. 95% of what they do is identical. Particular, being bolted into a compositor that wasn't ground-up programmed for 3D has to do odd things.
So, to make a point emitter in Particular, you have to grab a scene light. Point lights emit in all directions, spotlights emit in a cone. Hitfilm, you'd just create a point emitter and give it a trajectory...and it's that kind of nitpicky detail I'm not getting into.
Long story snarky, there are online manuals for CC Particle World, Particular and Hitfilm. If one really wants to get into the nitty gritty details one can open up three browser tabs.