Settings: f/16, 20 seconds, ISO 100, 35mm focal length
Set up. With the camera on a tripod positioned on a bridge over the motorway. Turn IS off, mirror lock on, focus a third of the way into the frame & then switch AF off. Keep the ISO low & in TV mode have the shutter open for as long as it takes the cars to enter & exit the frame. You may require exposure compensation depending upon how light the resulting image is. I also used the 2 second shutter delay function to avoid any camera shake.
Opinion. I’ve been wanting to try this for a while. Winter is definitely the prefered time of year to attempt this technique as the short days mean you can coincide the sun setting with peak traffic times. I like the effect of the car indicating to come off the motorway resulting in dashed yellow lights on the left of the red trail.