Other Tips
On Saturday the trains run every 8-10 minutes so you may have to wait a little while to capture your image. I took multiple shots in order to achieve the right amount of blur for the final effect. Try using different shutter speeds to capture different streaks of train and light. You may find that you like longer or shorter exposures than my image.
If you want to capture images on the “El” platform you may need approval from the Chicago Transit Authority. If you shoot without a tripod, you can get away with shooting on the platform, but the minute you pull out a tripod you will most likely be “greeted” by a few CTA employees. If you are interested in obtaining a permit you can find out more information at the link below. You will have a better chance of shooting without being bothered early in the morning or on the weekend.
http://www.transitchicago.com/business/photopolicy.aspx
The green circle on the map below is the location where the “S” Curve photo was taken. It’s a public parking lot that is free if you are traveling by foot. I looked at the view from different floors but in the end I decided to take the photo from the 4th floor. This level is just above the tracks of the “El” and provides a good vantage point to capture the image. There are open glassless windows on each floor that allow you to set up your camera even in bad weather.
The blue location on the map is another parking garage in the area that has a great vantage point of the same S curve. I’ve been to the roof of this garage but not to capture this image. This could be an interesting spot to capture a similar image from the other direction with the city