The Canon Speedlite 600EX-RT is a radio controlled camera flash that collided with the 21st century to bring high-tech to lighting. It has onboard a 2.4GHz radio trigger operating system used primarily by wedding and portrait photographers giving them full remote command of the flash.
Physically the flash weighs in at a hefty 18.7 oz. and measures in at 3.3”x5.6”x4.9”. It is powered by 4 AA batteries with an optional external battery pack holding 8-AA batteries for and additional $150.00. The flash automatically goes into standby mode after 90 seconds to conserve battery life and comes back to life when you hit the shutter button. It has a flip-down diffuser for smaller lenses, manual power mode, wireless optical and radio control and programmable lights and colors that can be seen from a distance to help determine if all systems are operating. It is compatible with all Canon cameras.
The Canon Speedlite 600EX-RT is capable of managing up to 15 flashes in groups of 5 and can actually trigger up to 15 different cameras via the remote! The size of the flash makes it quite bulky to be used on top of your camera but it can be done even with the extra pound of weight. This flash is designed more for stand-alone functions and professionals who need and can use small battery powered and remote controlled flashes such as wedding photographers.
While well powered and able to perform flash after flash with a zippy 2.5 second recovery, it is susceptible to overheating as many flashes are but it does have the programmable lighting to warn of this situation. It is quite silent in its operation and doesn’t jump or vibrate when fired. The brightness of the flash doesn’t diminish with repetitive use or low battery.
The bounce of the flash, the ability to bounce the light of other things such as ceilings and walls, is 0 to 90 degrees up, -7 degrees down, -180 degrees to the left and +90 degrees to the right. The Canon Speedlite 600EX-RT provides plenty of light in bounce situations.
The radio portion of the flash is rated to 100 feet with 2.405-2.475 GHz, 15 channels, 10,000 wireless ID’s to be combined with other photographers and not get confused, 5 group settings and the batteries will run up to 9 hours if you use the flash as a “commander” without the flash firing. Using the flash significantly reduces battery life.
The biggest complaint of the Canon Speedlite 600EX-RT is the poorly designed LCD screen. It is very tiny and jammed with information making it hard to program and harder to read.
Overall the Canon Speedlite 600EX-RT is an excellent professional flash best used as a stand-alone versus camera mounted due to the weight. The radio control is outstanding and very beneficial to wedding photographers who have lighting assistants to help set it up or multiple units. At $499.00 MSRP these are great for professionals but other models exist that fit on camera better like the Canon 430EX II that do an almost equally good job.