By Michael Corsentino

It’s an exciting time for the Canon Speedlite community. Canon’s new radio-enabled 600EX-RT Speedlite and companion ST-E3-RT radio transmitter are a quantum leap forward in wireless E-TTL handheld flash technology. It’s a safe bet other handheld flash manufactures will soon follow suit.

Replacing the 580EX II in Canon’s lineup as their flagship Speedlite, the 600EX-RT and ST-E3-RT both have built-in 2.4-GHz radio transmitters for wireless E-TTL and manual flash communication. The 600EX-RT also carries over wireless optical (IR) technology from the previous generation, making it fully backward compatible with the 580EX, 580EX II, 430EX, 430EX II, 320EX, and 270EX II, which are exclusively optical based. Wireless control must be either all optical or all radio, not a mixture of both.

Regarding compatibility, full access to the in-camera wireless external Speedlite menu controls requires a 2012 or later EOS camera model, such as the 5D Mark III or 1D X. This isn’t a problem due to the much-improved, easier-to-navigate menu system on the 600EX-RT and ST-E3-RT. Contrary to Canon’s published documentation, wireless high-speed sync does work up to 1/8000. on a 5D Mark II and 60D. Pre-2012 EOS model cameras will experience a 1-stop reduction in the maximum sync speed available for flash when using radio-enabled wireless E-TTL.

Optical triggers rely on unobstructed line-of-sight for successful communication between master and slave flashes, have a limited range of approximately 30′, and spotty performance in bright sunlight. Radio triggers have no such limitations: their signals pass easily through walls, doors, and windows, and can travel around corners and much longer distances. These features make radio communication significantly more reliable and desirable for wireless off-camera flash.

The 600EX-RT and ST-E3-RT have many new robust features, including 98′ of radio range, remote power control of up to 5 separate Speedlite groups or 15 individual Speedlites, 15 radio channels, and personal pin numbers for channels in multiple shooter/trigger environments. You can also mix Speedlites in both E-TTL and Manual modes, and remotely power on/off individual Speedlites (to easily see the affect of each light). A Link light confirms communication between the master and slave units, a ready light confirms all slaves are ready to fire, and you can perform remote camera firing.

In a stroke of usability genius, the engineers at Canon made the ST-E3-RT an almost exact duplicate of the 600EX-RT except for the missing flash. Once you’ve learned one piece of equipment you’ve learned them both.

The ST-E3-RT’s lack of a built-in AF-Assist Beam like the one on the ST-E2 means photographers working in low-light situations will likely want an additional 600EX-RT to use on-camera for the built-in AF-Assist Beam.

Other significant improvements include:

Zoom: Increased range is now 20–200mm

LCD: 40% larger LCD with larger, more legible dot matrix text, and choice of green or orange background colors (useful for assigning different colors to master and slaves).

GUI: Combined with the LCD and buttons, this is a vastly improved user interface with straightforward menu navigation. Menu items no longer jump around but instead appear in the same places making them much easier to find. Custom functions now have easy-to-understand menu descriptions.

Buttons: New dedicated one-button access to wireless functions and a lock switch to help safeguard settings. Confusing multifunction buttons have been replaced with four function buttons, each with one use. Button functions change interactively depending on the mode or screen you’re in. There’s also a larger Mode button for accessing all five flash modes.

Build: Weather sealing to match 1D X, improved hot shoe contacts, and more rugged case.

Power: Increased GN (guide number) to 197′ (60m) at ISO 100.

Filters: Includes filters, filter holder, and case.

All things considered, these babies are a dream come true -- albeit an expensive dream at US$629 for the 600EX-RT and $329 (street price) for the ST-E3-RT transmitter. The good news is no additional equipment is needed for wireless E-TTL and manual radio communication between your Speedlites. The built-in radio transmitter also means less stuff to carry, fewer batteries to buy, and fewer systems to troubleshoot.

Both units are dead simple to operate and work brilliantly straight out of the box. Along with the built-in radio capabilities, new and improved feature set, and streamlined interface, the Canon 600EX-RT and ST-E3-RT are a really exciting combination and worthy of consideration for those interested in upgrading or entering the world of wireless off-camera flash.

Price: 600EX-RT: $629.99; ST-E3-RT: $470

Web: www.usa.canon.com

Hot: Built-in wireless radio; increased zoom; improved interface

Not: ST-E3 lacks AF Assist Beam and optical wireless\

Rating: 8 out of 10

(This review is brought to you courtesy of "Layers Magazine": http://layersmagazine.com/ .)