04-21-2019, 11:42 PM
It appears there is something that changes with the Force ops built in Noise when you have negative frames for preroll on your timeline. This is most visible when you use Turb noise type, very low strength and have Frequency over 1.0. I have a Force set to continuous with both some low value gravity as well as Noise in both layers, and the movement pattern of the particles shifts very distinctly when the timeline hits frame 0. Before frame 0 the noise speed seems too high or something. Let me know if you need an example scene that shows the issue. Thanks.