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Lifewire / Jonno Hill
Excellent build quality
Overkill for some users
The Canon Speedlite 430EX III-RT Flash is a nearly perfect mid-size flash, but only for those shopping for the full suite of features on offer.
The Canon Speedlite 430EX III-RT Flash is a full-featured speedlight that will cover just about all the bases most users will want in a camera-mounted flash. We particularly enjoyed the modest, portable design and rock-solid build quality. Overall, there’s a lot to celebrate in this mid-size solution from Canon, but you will have to pay an appropriate price for the privilege.
The first thing we noticed about the Canon Speedlite 430EX III-RT Flash was the superb build quality. It still features plastic construction around the body, but something about it just feels extremely solid in your hand. The flash head gives users 90 degrees of vertical tilt and 330 degrees of horizontal rotation, letting you angle the flash nearly anywhere you like. All this is done by pressing the bounce lock release button (written as “PUSH” on the side of the flash head). By default, movement of the flash head is restricted until this button is depressed.
The Canon Speedlite 430EX III-RT Flash is a full-featured Speedlite that will cover just about all the bases most users will want in a camera-mounted solution.
On the side of the device, you’ll find the battery compartment cover, which opens to reveal room for four AA batteries, for which the position s clearly marked in a photo immediately underneath. On the front of the device, users will see the optical transmission wireless sensor and AF-assist beam emitter, and beneath the flash head itself, a bounce adapter detector and color filter detector.
On the bottom by the hot shoe, Canon has a unique lock lever and release button, which we greatly preferred to nearly all the other locking systems that similar products tend to have.
Finally, on the rear of the device, you’ll find the LCD screen, and the buttons and toggles necessary for operation, which we will cover in greater depth in the following section.
The Canon Speedlite 430EX III-RT Flash contains a wealth of features and controls. This is wonderful for those that need it, but it also required a considerable amount of manual-reading before we were familiar with how to access and control all these features.
The Canon Speedlite 430EX III-RT Flash contains two “on” states, controlled by the power switch on the rear of the device. Both the “LOCK” and “ON” modes turn the power on, but the “LOCK” mode disables any control, instead displaying a message on-screen when trying to press any of the buttons.
It also required a considerable amount of manual-reading before we were familiar with how to access and control all these features.
Upon startup, and between uses, the flash displays a charging progress bar in the upper right corner of the display. When the flash is ready to use again, the physical indicator on the left of the rear illuminates red.
One of the more interesting features is the Speedlite icon in the display. It looks fairly simple at first glance, but it actually contains a wealth of information, displaying subtle difference to distinguish between guide number priority, bounce orientation, whether the bounce adapter or color filter are attached, and even if the flash is overheating and restricted due to temperature.
The Canon Speedlite 430EX III-RT Flash contains two overarching modes: Manual and ETTL, enabling fully automatic flash photography. TTL, or Through The Lens, is a metering mode that lets a flash unit fire a series of infrared bursts and evaluates the actual light coming through the lens to determine how much power to deliver when taking a photo. This can be useful in situations where photographers want to be able to get appropriately lit shots without fiddling too much with controls, especially when the subject isn’t something you can control. Canon’s particular flavor of TTL did an admirable job properly exposing subjects in a variety of scenarios during our testing.
In Manual mode, the Canon Speedlite 430EX III-RT Flash does have a few more tricks up its sleeve than its more barebones counterparts
If you are using this flash on a Canon camera body, the flash can also automatically detect the focal length of the lens you are using and adjust the flash coverage to compensate. If you’re not using a Canon camera, you still have the option to manually set the focal length (from 24 to 105mm).
In Manual mode, the Canon Speedlite 430EX III-RT Flash does have a few more tricks up its sleeve than its more barebones counterparts. For example, in radio transmission mode, the flash can function as a trigger to other controlled devices. Furthermore, you can still make use of the ETTL functionality, as long as you are pairing the 430EX III-RT with additional identical units. The settings determined by the master unit on the camera are automatically sent and applied to slave devices.
Out of the box, the Canon Speedlite 430EX III-RT Flash is ready for use as soon as you insert the required four AA batteries. In the case of autoflash use, very few additional steps are required to start using the flash. However, due to the extremely intricate options, modes, and functions present on the device, you’ll probably want to consult the manual before they try to begin using the device.
This is one of the only areas we can really dock points from Canon. While many users might be purchasing this flash specifically for the wealth of functionality, we would have liked to see a little bit more intuitive controls and menus.
Canon isn’t going to save you a ton of money at the 430EX III-RT’s MSRP of $299.99, but it’s still a considerable discount from its full-figured cousin the 600EX, which costs buyers nearly twice as much. Ultimately the price is in line with what we’ve seen from similar reputable name brands in the industry, albeit more expensive than some Chinese counterparts.
The Canon Speedlite 600EX II-RT Flash asks for a lot more money than the 430EX III-RT, but it also gives a lot more as well. The 600EX II-RT is considerably brighter, features a wider angle of coverage, and allows for better off-camera control. The 430EX III-RT doesn’t lose everywhere, however. It features a smaller body, shorter recycle time (time between flashes), more wireless communication channels, and a lighter body. Ultimately these are different flashes that will be appealing to different users, but they are both very capable.