Finally with the arrival of the Speedlite Transmitter ST-E3-RT, Canon has upgraded its offerings to include a radio speedlite trigger.
They were overdue to take advantage of a superior technology that is available and this accessory is packed full.
The ST-E3-RT uses 2-way wireless radio for improved communication among the master and slave flash units.
One transmitter can control up to 5 groups of flashes (or 15 separate flashes) and has 8 types of custom functions.
That includes controlling the light ratio in half-stop increments up to a ratio of 8 : 1.
The LCD screen with back-lighting control is a bright dot matrix display that gives you all the information you could possibly need.
You can adjust the LCD screen to 5 different levels of contrast.
You can set the background color of the screen to green or Amber if it is set as the master unit.
It has almost a 100 foot range with 360 degree coverage.
This supports E-TTL II (evaluative through the lens) metering as well as manual and strobe flash.
The ST-E3-RT works with the Canon Speedlite 600EX-RT. It has all of the same control functions as a 600EX-RT, except of course the flash itself.
This photo shows you the transmitter mounted on top of a Canon 5D Mark III.
What I like about these speedlite transmitters is how light and small they are.
I have had a Canon Speedlite Transmitter ST-E2 for many years now and your camera is still light and easy to handle with the transmitter attached.
I also like the fact that you can power this accessory with with two AA batteries.
The RT (Radio Transmitter) system is almost a necessity when you are shooting with speedlites inside soft-boxes or other similar systems where direct line-of-site is interrupted.
This transmitter also has the same dust and water resistance that has been built into the Canon EOS-1D series of cameras.
You can get more insightful information about this Canon accessory by reading the Speedlite Transmitter ST-E3-RT Speedlite Manual pdf.
There are rumors that Canon will be announcing replacement flash for the IR (infra-red) triggered Canon Speedlight 430EX II. with RT- Radio Transmitter control.
Have a blast with your speedlites.
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