Another method for creating an abstract is to rotate the lens during a long exposure. I used this technique to capture of photograph of some light bulbs on the wall of the MGM Grand in Las Vegas. I attached the Nikon 70-200 VR2 to the tripod. I then loosened the tripod collar on the lens so that I could spin the lens freely.
The shutter speed for this picture was 3 seconds. During the exposure, I rotated the lens at different rates--checking the LCD panel to see which effect was most effective. Finally, I used multiple exposures to add another element to this abstract image.
Spinning points of light abstract