Good question! The automatic setting selection is a great feature of the Instax Mini 9 and most of the time it does a good job of choosing the best setting for the level of light exposure in which you are shooting.   That being said, there are times when you will see that the photo is under or overexposed in which case you can experiment with choosing a different setting: Overall, I have found that the Sunny, Slightly Cloudy mode gives the best photos with the Mini 9. What I like about this setting is that it gives a well-balanced photo with good detailing in both the foreground and background If you find that your photos are coming out too dark, try turning the dial down one click e.g. if the illuminated setting is Sunny and Bright try changing the setting to Sunny, Slightly Cloudy. Similarly, if your photos are too bright try turning the dial-up one-click e.g. if the illuminated setting is Sunny, Slight Cloudy try changing the setting to Sunny and Bright.