I've got a popnet that is scattering over geometry with constant birth rate and a 2 second life expectancy. When the first particle dies at the 60 frame mark, suddenly all the point numbers begin to change every frame.

This is causing problems as I am using the point numbers to do a copy stamp.

What am I doing wrong? Is there a way to make the points keep their number at least until each one dies?

In your copy sop use @id instead of @ptnum. Point numbers are reused when points are deleted/die, particle ids are not.

Great, thanks kemijo!