Hi all could really do with some help... I found a video on youtube that shows beautiful light trails: http://www.youtube.com/watch?v=uyhKhCFklVI&NR=1&feature=fvwp Im trying to do this in houdini however when i instance lights to particles the rendering takes ages... The video tutorial for maya seems to be extremely fast am i going the correct way about this using particles ? How could this be setup to be fast Thanks Light_Streaks.hipnc