Well, the exposure is fairly simple. Set the flash on "rear sync", then let the camera-exposuremeter decide the time and then is it just to follow your "target" with the camera until the flash goes of, that creates the effect.
By the way, the aperture were set at f11, to create the motionlike effect...
Christian, Thanks so much for putting this image up and with the exposure data too (the aperature does look a bit off). I have a similar photo in my portfolio, but had asked for some assistance on taking similar photos as I felt I could have done better. Thoughts? Great shot, love the strength of the red in the photo. Good shutter speed to capture the dramatic-ness of the fire trails. Russell
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