I took a photo without flash at night, with fast moving object. Everything exposed normal, but those two people have strange artefacts like shadows of themselves and not smooth moving and not smooth moving like I see on other fast moving object photos (smooth, smudged movement).
I have Nikon F3, ISO was 400, aperture mode, 35mm at f/2, shutter speed I don't remember (sorry).
Ice park by Svjetlopisac, on Flickr
What happened? Is my shutter OK? :/