Radio triggering is more reliable than optical triggering because it is less prone to interference from other devices. This makes it more suitable for use where there could be other photographers operating in your vicinity.
Automatic exposure via E-TTL II and high speed sync are two compelling features made possible by this transmitter. Without high speed sync, strobe photography is often limited to shutter speeds of 1/125s or 1/200s. With high speed sync, you can often use the fastest shutter speed on your camera. This is ideal for expanding your creative freedom in using lenses with large maximum apertures without requiring you to use ND filters.
The following items are included when you hire the Canon Speedlite Transmitter ST-E3-RT:
Learn more about the Canon Speedlite Transmitter ST-E3-RT on the official product page.