i have a question about night shots, i follow a small group of street entertainers, their big thing is fire. fire eating/breathing/juggling/ect. i was wondering whats the best way to capture them at night. ive noticed that if i my shutter speed is too fast i cant seem to get the nice trail effect, but if its to slow the performer becomes too blurry. i shoot with a nikon d200 and a sigma 18-125 3.5-6.5 lens. i have an sb-600 speedlight. is there a any tricks to get a nice clean shot without getting my subject blurry?