Using External Electronic Flash

Canon offers a broad range of accessory electronic flash units for the EOS 7D. They can be mounted to the flash accessory shoe, or used off-camera with a dedicated cord that plugs into the flash shoe to maintain full communications with the camera for all special features. (Non-dedicated flash units, such as studio flash, can be connected using the PC terminal.) They range from the Speedlite 580EX II (see Figure 10.21), which can correctly expose subjects up to 24 feet away at f/11 and ISO 200, to the 220EX, which is good out to 9 feet at f/11 and ISO 200. (You’ll get greater ranges at even higher ISO settings, of course.) There are also two electronic flash units specifically for specialized close-up flash photography.

Figure 10.21. The Canon Speedlite 580EX II is the most powerful shoe-mount flash Canon offers.