I am doing a production for a school one-act contest. No pyro allowed. I need a poof of smoke from a magic spell that a character will appear in. The actor can produce the smoke but I can't have crew members on stage (even hidden). This needs to happen several times during the show so I need to be able to repeat it. I'm looking at smoke paper but I'm worried this won't really be enough effect or canned fog but I'm worried this will dissipate too quickly. I have a fog machine but it's loud and slow and the smoke lingers too long. Any suggestions? Cheap is good but I have a little money to spend if needed. Thanks!