Flash Options on a Canon EOS Rebel T3 Series Camera
When you set the Mode dial on your Canon Rebel T3 or T3i to P, Tv, Av, M, or A-DEP, Shooting Menu 1 offers a Flash Control option. Using this menu item, you can adjust flash power (although using the Quick Control screen is easier). The Flash Control option also enables you to customize a few other aspects of the built-in flash as well as control an external flash head.
To explore your options, highlight Flash Control and press Set. Here’s the rundown of the available options:
Flash Firing: Normally, this option is set to Enable. If you want to disable the flash, you can choose Disable instead. However, you don’t have to take this step in most cases — just close the pop-up flash head on top of the camera if you don’t want to use flash.
E-TTL II Metering (T3i only): This option enables you to switch from the default flash metering approach, called Evaluative. In this mode, the camera exposes the background using ambient light when possible and then sets the flash power to serve as fill light on the subject.
If you instead select the Average option, the flash is used as the primary light source, meaning that the flash power is set to expose the entire scene without relying on ambient light. Typically, this results in a more powerful (and possibly harsh) flash lighting and dark backgrounds.
Built-in Flash Function Setting: If you highlight this option and press Set, you display the screen shown here.
But which options are adjustable on the T3i depends on whether you set the first option, Built-in Flash, to Normal Firing, or to one of the two settings that set the built-in flash to trigger off-camera flash units.
The other options available for normal flash operation work like so:
Shutter Sync: By default, the flash fires at the beginning of the exposure. This flash timing, known as 1st curtain sync, is the best choice for most subjects. However, if you use a very slow shutter speed and you’re photographing a moving object, 1st curtain sync causes the blur that results from the motion to appear in front of the object, which doesn’t make much visual sense.
To solve this problem, you can change the Shutter Sync option to 2nd curtain sync, also known as rear-curtain sync. In this flash mode, the motion trails appear behind the moving object. The flash fires twice in this mode: once when you press the shutter button and again at the end of the exposure.
Flash Exposure Compensation: This setting adjusts the power of the built-in flash.
The T3 has four options affecting the flash here. Shutter Sync and Flash Exposure Compensation are joined by
Flash Mode: Ignore this; it’s not adjustable when you use the built-in flash.
E-TTL II Metering: See above.
External Flash controls: The last three options on the Flash Control list relate to external flash heads; they don’t affect the performance of the built-in flash. However, they apply only to Canon EX-series Speedlites that enable you to control the flash through the camera. If you own such a flash, refer to the flash manual for details.
You can probably discern from these descriptions that most of these features are designed for photographers schooled in flash photography who want to mess around with advanced flash options.