I think it was the first technique I tried when I learned about it and I’d like to show you one of the pictures I used the technique called Slow Sync Flash. This technique combines a slower than normal shutter speed with a flash during the exposure I mean combining flash with long exposures. When the flash fires during exposure… With Second Curtain Synch (also sometimes called Slow Synch). The shutter opens and the lights record their streaks. Then the flash illuminates the subject. The streaks from the lights lead up to the subject, giving the illusion of speed and creating a generally interesting effect. I used the typical “zoom in” “zoom out” sync flash thing, you also can use only the flash and long exposure without moving the camera or the lens… For my personal taste it´s a little bit exaggerated but they loved it and now they have a 50×60 cm picture in their living room… imagine.
Well it depends on the speed and direction of movement and the intensity of the lights, second curtain synch requires some practice, a bit of finesse and sometimes luck to use well. And with digital you can review your results immediately and try something different if you didn’t get what you were expecting.