When there is light, such as the sun or a bright window, behind your subject, the AE-1's meter may be overinfluenced by that light and your subject will come out too dark. In order to give correct exposure to your subject, press the backlight control switch (3) and hold it in until after you press the shutter button (14). This will give the subject 1 1/2 f/stops more exposure. Using the backlight control switch may also help you expose your subject correctly when it is surrounded by bright snow or a sandy beach in summer.