Your slave
units may come with stands, so they can be used independently of your camera.
The Canon Speedlite ST-E2 Transmitter is used to trigger up to two slave, or remote, Speedlite flashes that are not wired into acamera. The ST-E2 connects to a camera wirelessly via the hotshoe on top of a camera. This transmitter functions uses infrared waves and thus only works with direct line of sight outdoors. All Canon SLR cameras accept the ST-E2, and a number of non-SLR models also have compatible hotshoes.
Instructions
1. Add a battery to your ST-E2. It takes a 2CR5-type battery, which might be difficult to find in stores and is not included with the unit. It can be ordered through major battery manufacturers such as Duracell and Energizer, some office supply stores, or major e-commerce sites such as Amazon and Overstock.
2. Attach the unit to your Canon camera hotshoe. Slide the transmitter onto your hotshoe, with the red face of the transmitter facing away from you as you hold the camera. Use the circular wheel to lock the transmitter in place, so that it does not fall off. If the transmitter does not initially slide into place, you might need to loosen the circular locking wheel.
3. Turn on the transmitter using the power switch on the lower-right side of the control face. Slide the switch from the "O" (off) to the "I" (on) setting. The "Hold" setting locks settings made in the "I" setting.
4. Turn on your slave Speedlite unit(s). Switch your slave(s) to "slave" mode, and dial in your desired flash power settings. Depending on the effects you want to create, you could, for example, use full power for one Speedlite and 1/4 power for another Speedlite. The method used for setting power output differs among Speedlite models.
5. Set your camera to the desired exposure mode. Use "Program" mode for automatic exposure, "Aperture priority" for fill flash or "Manual" for total control over your exposure.
6. Press the "pilot" button on the transmitter, or take a picture to verify that your trigger is functioning. All slave flashes should fire if your setup is functioning properly.
Tags: Canon Speedlite, your camera, your slave