Canon EOS 5D Mark III EOS 5D Mark III Instruction Manual - Page 172

F: Bulb Exposures When bulb is set, the shutter stays open as long as you hold down the shutter button completely, and closes when you let go of the shutter button. This is called bulb exposure. Use bulb exposures for night scenes, fireworks, the heavens, and other subjects requiring long exposures. 1 Set the Mode Dial to . 2 Set the desired aperture. While looking at the LCD panel, turn the or dial. 3 Take the picture. While you hold down the shutter Elapsed exposure time button, the exposure will continue. X The elapsed exposure time will be displayed on the LCD panel. Long exposures produce more noise than usual. When [z3: Long exp. noise reduction] is set to [Auto] or [Enable], noise generated by the long exposure can be reduced (p.144). For bulb exposures, using a tripod and Remote Switch RS-80N3 (sold separately) or Timer Remote Controller TC-80N3 (sold separately) is recommended (p.185). You can also use a remote controller (sold separately, p.186) for bulb exposures. When you press the remote controller's transmit button, the bulb exposure will start immediately or 2 sec. later. Press the button again to stop the bulb exposure. 172