The GW-7900 has a nice bright and greenish EL backlight. You can choose between a 1.5 second and a 3 seconds backlight. The watch has also a Full Auto Illuminator on-board. When activated (press the light button for about 3 seconds) the EL backlight will turn on in the dark when you tilt your arm about 45 degrees towards you, while your arm is parallel to the ground.
Above photo's taken during the "Kustmarathon 2012" by Eva
Above photo's taken during the "Kustmarathon 2012" by Bram
View from my bike at kilometer 33.Further more, the watch has a Power Save function (default toggled on), which turns off the display in the dark after about an hour (60 to 70 minutes). If the watch is more than a week in PS mode, it will also stop to receive the Atomic Clock signals. In Time Keeping mode you can display the chosen World Time in the upper display, which can be handy if you have correspondence n other time zones.