This week’s question is from Sarah who asked, “If my flash already has built in wireless controls, why do I need to get a wireless trigger like a Pocket Wizard?” When it comes to controlling your flash wirelessly, there are two primary technologies: One is by infrared and the other by radio.

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Infrared Technology

Compared to systems that use radio frequencies, ones that use infrared technology are generally a cheaper and simpler solution to implement. This is largely due to the fact that laws regulating radio and audio transmission are different around the world, hence radio units need to be designed for each region’s governing laws. This is also why some of the more advanced flashes, such as a Nikon SB-900 or Canon’s 580 EX II, only offer built-in infrared wireless controls rather than radio.


However, a large benefit of infrared is that the technology allows the communication of TTL or manual control information between the master and slave flash units. This means you are able to adjust all your remote flashes right from your camera, or on-camera flash.

Although it is possible to adjust all your remote flashes in one place, the biggest downside of the master/slave set-up is that the infrared system requires all flashes to be in direct line of sight. In other words, if the master flash can’t see the slave flashes, the system does not work. Another big weakness of the infrared method is that their range is much more limited, and is also very unreliable in certain conditions such as bright sunlight, which can interfere with the infrared signals.

So, built-in infrared wireless technology is generally great to use in close range and indoor “studio-like” situations when direct line of sight is possible. So long as you have two or more name-brand flashes that are compatible with one another, such as Nikon’s CLS built in system, then you can start playing around with multiple flash setups without any additional hardware.

Radio Systems

Unlike the implemented infrared technology, radio flash triggers can effectively communicate with one another across hundreds, or even thousands of feet. Not only this, but they also do not require line of sight. This is a huge plus for those that shoot weddings, corporate or sporting events as often times our lights are setup hundreds of feet away with people and other objects in-between.

However, a big downside to having to radio technology is the need to buy multiple radios which can get quite expensive. Until recently, if we wanted radio triggers, we were stuck with 3rd party systems such as a Pocket Wizard, Radio Popper, or Yongnuo. Now, these systems are finally being built into advanced flash units, such as the Canon 600 EX-RT. This is definitely a good development, however, at $500 a piece they are quite pricey. It’s not cheap, but it is an option that’s available.


Another negative about the radio solution is that the features and functionality are not always the same. For example, some don’t offer any control of the flash unit itself, like the Pocket Wizard Plus III, while others offer hybrid infrared and radio systems that allow you to control your remote flashes, such as the Radio Popper.

pocket wizard


Overall, the radio trigger system is far more consistent and reliable, yet it is more expensive than infrared technology and may require additional hardware. It is also able to trigger across broad distances without direct line of site, and can be used effectively both indoors and outdoors, something the built-in infrared systems cannot do.

So, if you’re looking for a simple and cheap solution for a small indoor portrait shoot, the the built-in infrared system may work for you, so long as there are no objects placed between each flash. However, if you’re let’s say a wedding photographer, who needs a fast and reliable off-camera flash setup that can shoot across long distances and through objects, a radio triggering system is really your only option.

Hopefully these tips helped you understand the differences between the infrared vs. radio flash triggering systems! If you have a question you would like us to answer, feel free to send us a message to our e-mail: