To accomplish this create a metal cage for the steel wool. I just tied a string onto a metal whisk from the dollar store. Get size 0 steel wool and put about half a pad inside of the whisk. Set your camera on iso 100-200 and f4.0-6.3 (anything less will result in bad washout). Then set the shutter to 30-200 seconds depending on the ambient light of the night. Light the steel wool on fire trigger your shutter and start spinning.
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