About the best place you can go is the famous spot (see pictures below), near the Hilton Hotel.
When standing in front of terminal 9, you need to go to your left, go through the underpass and make a right. Keep walking till you see the hilton Hotel. (about 15 minutes). Across you will see the Sofitel where many shots have been taken. The best time is in the morning when the sun is in your back.
Click on the website below to see a map. You need to get to position 12.